[ { "id": "https://authors.library.caltech.edu/records/647rw-v5242", "eprint_id": 121712, "eprint_status": "archive", "datestamp": "2023-08-20 08:21:56", "lastmod": "2023-10-20 15:47:44", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lei-Mi", "name": { "family": "Lei", "given": "Mi" } }, { "id": "Fukumori-Rikuto", "name": { "family": "Fukumori", "given": "Rikuto" }, "orcid": "0000-0003-0896-4261" }, { "id": "Rochman-Jake-H", "name": { "family": "Rochman", "given": "Jake" } }, { "id": "Zhu-Bihui", "name": { "family": "Zhu", "given": "Bihui" }, "orcid": "0000-0002-9457-4560" }, { "id": "Endres-M", "name": { "family": "Endres", "given": "Manuel" }, "orcid": "0000-0002-4461-224X" }, { "id": "Choi-Joonhee", "name": { "family": "Choi", "given": "Joonhee" }, "orcid": "0000-0002-3507-8751" }, { "id": "Faraon-A", "name": { "family": "Faraon", "given": "Andrei" }, "orcid": "0000-0002-8141-391X" } ] }, "title": "Many-body cavity quantum electrodynamics with driven inhomogeneous emitters", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nWe thank A. Ruskuc, T. Xie, C.-J. Wu, O. Vendrell and R. Finkelstein for discussion. This work was supported by the US Department of Energy, Office of Science, National Quantum Information Science Research Centers, Co-design Center for Quantum Advantage (contract number DE-SC0012704), Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (PHY-1733907) with support from the Moore Foundation and by the Office of Naval Research awards no. N00014-19-1-2182 and N00014-22-1-2422 and the Army Research Office MURI programme (W911NF2010136). The device nanofabrication was performed in the Kavli Nanoscience Institute at the California Institute of Technology. M.L. acknowledges the support from the Eddleman Graduate Fellowship. R.F. acknowledges the support from the JASSO Graduate Scholarship. J.R. acknowledges the support from the Natural Sciences and Engineering Research Council of Canada (NSERC) (PGSD3-502844-2017). J.C. acknowledges support from the IQIM Postdoctoral Fellowship. \n\nThese authors contributed equally: Mi Lei, Rikuto Fukumori. \n\nContributions. A.F. conceived the experiment. M.L. and R.F. built the experimental set-up, performed the measurements and analysed the data. J.R. fabricated the device. M.L., R.F., B.Z., M.E., J.C. and A.F. interpreted the results. M.L., R.F., J.C. and A.F. wrote the manuscript, with input from all authors. All work was supervised by J.C. and A.F. \n\nData availability. The data that support the findings of this study are available from the corresponding authors on reasonable request. \n\nThe authors declare no competing interests.\n\n
Accepted Version - 2208.04345.pdf
", "abstract": "Quantum emitters coupled to optical resonators are quintessential systems for exploring fundamental phenomena in cavity quantum electrodynamics (cQED) and are commonly used in quantum devices acting as qubits, memories and transducers. Many previous experimental cQED studies have focused on regimes in which a small number of identical emitters interact with a weak external drive, such that the system can be described with simple, effective models. However, the dynamics of a disordered, many-body quantum system subject to a strong drive have not been fully explored, despite its importance and potential in quantum applications. Here we study how a large, inhomogeneously broadened ensemble of solid-state emitters coupled with high cooperativity to a nanophotonic resonator behaves under strong excitation. We discover a sharp, collectively induced transparency (CIT) in the cavity reflection spectrum, resulting from quantum interference and collective response induced by the interplay between driven inhomogeneous emitters and cavity photons. Furthermore, coherent excitation within the CIT window leads to highly nonlinear optical emission, spanning from fast superradiance to slow subradiance. These phenomena in the many-body cQED regime enable new mechanisms for achieving slow light and frequency referencing, pave a way towards solid-state superradiant lasers and inform the development of ensemble-based quantum interconnects.", "date": "2023-06-07", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20230605-255128000.2", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230605-255128000.2", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0012704" }, { "agency": "NSF", "grant_number": "PHY-1733907" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-19-1-2182" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-22-1-2422" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF2010136" }, { "agency": "Eddleman Quantum Institute" }, { "agency": "Japan Student Services Organization (JASSO)" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)", "grant_number": "PGSD3-502844-2017" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "primary_object": { "basename": "2208.04345.pdf", "url": "https://authors.library.caltech.edu/records/647rw-v5242/files/2208.04345.pdf" }, "pub_year": "2023", "author_list": "Lei, Mi; Fukumori, Rikuto; et el." }, { "id": "https://authors.library.caltech.edu/records/ywb8x-41903", "eprint_id": 121380, "eprint_status": "archive", "datestamp": "2023-08-20 08:16:24", "lastmod": "2023-10-20 15:26:38", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Joshi-Chaitali", "name": { "family": "Joshi", "given": "Chaitali" } }, { "id": "Chen-Wenyuan", "name": { "family": "Chen", "given": "Wenyuan" } }, { "id": "LeDuc-Henry-G", "name": { "family": "LeDuc", "given": "Henry G." } }, { "id": "Day-Peter-K", "name": { "family": "Day", "given": "Peter K." } }, { "id": "Mirhosseini-M", "name": { "family": "Mirhosseini", "given": "Mohammad" }, "orcid": "0000-0002-9084-6880" } ] }, "title": "Strong kinetic-inductance Kerr nonlinearity with titanium nitride nanowires", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nThis work was supported by startup funds from the Caltech EAS division, a Braun trust grant, and the National Science Foundation (grant No. 1733907). C.J. gratefully acknowledges support from the IQIM/AWS Postdoctoral Fellowship. We acknowledge Niv Drucker from Quantum Machines for software support while performing the cavity ringdown measurements.\n\nSubmitted - 2208.00317.pdf
", "abstract": "Thin films of disordered superconductors such as titanium nitride (TiN) exhibit large kinetic inductance (KI), high critical temperature, and large quality factors at the single-photon level. KI nonlinearity can be exploited as an alternative to Josephson junctions for creating novel nonlinear quantum devices with the potential to operate at higher frequencies and at elevated temperatures. We study a means of magnifying KI nonlinearity by confining the current density of resonant electromagnetic modes in nanowires with a small volume V \u2243 10\u207b\u2074 um\u00b3. Using this concept, we realize microwave-frequency Kerr cavities with a maximum Kerr-shift per photon of K/2\u03c0 = 123.5 \u00b1 3 kHz and report a nonlinearity-to-linewidth ratio K/\u03b3 = 21%. With improved design, our devices are expected to approach the regime of strong quantum nonlinearity in the millimeter-wave spectrum.", "date": "2023-05-15", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20230512-186482000.3", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230512-186482000.3", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Division of Engineering and Applied Science" }, { "agency": "Carl F. Braun Trust" }, { "agency": "NSF", "grant_number": "PHY-0757058" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "AWS-Center-for-Quantum-Computing" } ] }, "primary_object": { "basename": "2208.00317.pdf", "url": "https://authors.library.caltech.edu/records/ywb8x-41903/files/2208.00317.pdf" }, "pub_year": "2023", "author_list": "Joshi, Chaitali; Chen, Wenyuan; et el." }, { "id": "https://authors.library.caltech.edu/records/48j57-wte35", "eprint_id": 121378, "eprint_status": "archive", "datestamp": "2023-08-20 08:54:51", "lastmod": "2023-10-20 15:26:33", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Joshi-Chaitali", "name": { "family": "Joshi", "given": "Chaitali" } }, { "id": "Yang-Frank", "name": { "family": "Yang", "given": "Frank" }, "orcid": "0000-0001-5591-4035" }, { "id": "Mirhosseini-M", "name": { "family": "Mirhosseini", "given": "Mohammad" }, "orcid": "0000-0002-9084-6880" } ] }, "title": "Resonance fluorescence of a chiral artificial atom", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nThis work was supported by startup funds from the Caltech EAS division, a Braun trust grant, and the National Science Foundation (grant No. 1733907). C.J. gratefully acknowledges support from the IQIM/AWS Postdoctoral Fellowship. F.Y. gratefully acknowledges support from the NSF Graduate Research Fellowship.\n\nSubmitted - 2212.11400.pdf
", "abstract": "We demonstrate a superconducting artificial atom with strong unidirectional coupling to a microwave photonic waveguide. Our artificial atom is realized by coupling a transmon qubit to the waveguide at two spatially separated points with time-modulated interactions. Direction-sensitive interference arising from the parametric couplings in our scheme results in a non-reciprocal response, where we measure a forward/backward ratio of spontaneous emission exceeding 100. We verify the quantum nonlinear behavior of this artificial chiral atom by measuring the resonance fluorescence spectrum under a strong resonant drive and observing well-resolved Mollow triplets. Further, we demonstrate chirality for the second transition energy of the artificial atom and control it with a pulse sequence to realize a qubit-state-dependent non-reciprocal phase on itinerant photons. Our demonstration puts forth a superconducting hardware platform for the scalable realization of several key functionalities pursued within the paradigm of chiral quantum optics, including quantum networks with all-to-all connectivity, driven-dissipative stabilization of many-body entanglement, and the generation of complex non-classical states of light.", "date": "2023-05-13", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20230512-186140000.1", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230512-186140000.1", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Division of Engineering and Applied Science" }, { "agency": "Carl F. Braun Trust" }, { "agency": "NSF", "grant_number": "PHY-1733907" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "AWS Center for Quantum Computing" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "AWS-Center-for-Quantum-Computing" } ] }, "primary_object": { "basename": "2212.11400.pdf", "url": "https://authors.library.caltech.edu/records/48j57-wte35/files/2212.11400.pdf" }, "pub_year": "2023", "author_list": "Joshi, Chaitali; Yang, Frank; et el." }, { "id": "https://authors.library.caltech.edu/records/0h81w-59223", "eprint_id": 121364, "eprint_status": "archive", "datestamp": "2023-08-20 08:15:05", "lastmod": "2023-10-20 15:26:12", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bozkurt-Alk\u0131m-B", "name": { "family": "Bozkurt", "given": "Alk\u0131m" }, "orcid": "0000-0003-0633-8902" }, { "id": "Zhao-Han", "name": { "family": "Zhao", "given": "Han" } }, { "id": "Joshi-Chaitali", "name": { "family": "Joshi", "given": "Chaitali" } }, { "id": "LeDuc-Henry-G", "name": { "family": "LeDuc", "given": "Henry G." } }, { "id": "Day-Peter-K", "name": { "family": "Day", "given": "Peter K." } }, { "id": "Mirhosseini-M", "name": { "family": "Mirhosseini", "given": "Mohammad" }, "orcid": "0000-0002-9084-6880" } ] }, "title": "A quantum electromechanical interface for long-lived phonons", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Oskar Painter and Mahmud Kalaee for fruitful discussions, which led to the conception of this work. This work was supported by the startup funds from the EAS division at Caltech, National Research Foundation (grant No. 2137776), and a KNI-Wheatley scholarship. C.J. gratefully acknowledges support the IQIM/AWS Postdoctoral Fellowship. M.M gratefully acknowledges support from the Q-NEXT.\n\nSubmitted - 2207.10972.pdf
", "abstract": "Controlling long-lived mechanical oscillators in the quantum regime holds promises for quantum information processing. Here, we present an electromechanical system capable of operating in the GHz-frequency band in a silicon-on-insulator platform. Relying on a novel driving scheme based on an electrostatic field and high-impedance microwave cavities based on TiN superinductors, we are able to demonstrate a parametrically-enhanced electromechanical coupling of g/2\u03c0 = 1.1 MHz, sufficient to enter the strong-coupling regime with a cooperativity of C = 1200. The absence of piezoelectric materials in our platform leads to long mechanical lifetimes, finding intrinsic values up to \u03c4_d = 265 \u03bcs (Q = 8.4 \u00d7 10\u2076 at \u03c9\u2098/2\u03c0= 5 GHz) measured at low-phonon numbers and millikelvin temperatures. Despite the strong parametric drives, we find the cavity-mechanics system in the quantum ground state by performing sideband thermometry measurements. Simultaneously achieving ground-state operation, long mechanical lifetimes, and strong coupling sets the stage for employing silicon electromechanical resonators as memory elements and transducers in hybrid quantum systems, and as a tool for probing the origins of acoustic loss in the quantum regime.", "date": "2023-05-11", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20230510-141132000.2", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230510-141132000.2", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Division of Engineering and Applied Science" }, { "agency": "NSF", "grant_number": "OMA-2137776" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "AWS Center for Quantum Computing" }, { "agency": "Q-NEXT" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Kavli-Nanoscience-Institute" }, { "id": "AWS-Center-for-Quantum-Computing" } ] }, "primary_object": { "basename": "2207.10972.pdf", "url": "https://authors.library.caltech.edu/records/0h81w-59223/files/2207.10972.pdf" }, "pub_year": "2023", "author_list": "Bozkurt, Alk\u0131m; Zhao, Han; et el." }, { "id": "https://authors.library.caltech.edu/records/18j3d-jg202", "eprint_id": 120115, "eprint_status": "archive", "datestamp": "2023-08-20 08:02:04", "lastmod": "2023-10-25 16:53:05", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ferreira-Vinicius-S", "name": { "family": "Ferreira", "given": "Vinicius S." }, "orcid": "0000-0002-9522-2567" }, { "id": "Kim-Gihwan", "name": { "family": "Kim", "given": "Gihwan" } }, { "id": "Butler-Andreas", "name": { "family": "Butler", "given": "Andreas" } }, { "id": "Pichler-Hannes", "name": { "family": "Pichler", "given": "Hannes" }, "orcid": "0000-0003-2144-536X" }, { "id": "Painter-O", "name": { "family": "Painter", "given": "Oskar" }, "orcid": "0000-0002-1581-9209" } ] }, "title": "Deterministic Generation of Multidimensional Photonic Cluster States with a Single Quantum Emitter", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Eunjong Kim for helpful discussions regarding experimental setup, and we thank Mo Chen for his collaboration in fridge-related work. This work was supported by the AFOSR MURI Quantum Photonic Matter (grant 16RT0696), through a grant from the Department of Energy (grant DE-SC0020152), and through a sponsored research agreement with Amazon Web Services. V.F gratefully acknowledges support from NSF GFRP Fellowship.\n\nSubmitted - 2206.10076.pdf
", "abstract": "Multidimensional photonic graph states, such as cluster states, have prospective applications in quantum metrology, secure quantum communication, and measurement-based quantum computation. However, to date, generation of multidimensional cluster states of photonic qubits has relied on probabilistic methods that limit the scalability of typical generation schemes in optical systems. Here we present an experimental implementation in the microwave domain of a resource-efficient scheme for the deterministic generation of 2D photonic cluster states. By utilizing a coupled resonator array as a slow-light waveguide, a single flux-tunable transmon qubit as a quantum emitter, and a second auxiliary transmon as a switchable mirror, we achieve rapid, shaped emission of entangled photon wavepackets, and selective time-delayed feedback of photon wavepackets to the emitter qubit. We leverage these capabilities to generate a 2D cluster state of four photons with 70\\% fidelity, as verified by tomographic reconstruction of the quantum state. We discuss how our scheme could be straightforwardly extended to the generation of even larger cluster states, of even higher dimension, thereby expanding the scope and practical utility of such states for quantum information processing tasks.", "date": "2023-03-16", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20230316-224545724", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230316-224545724", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "16RT0696" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0020152" }, { "agency": "Amazon Web Services" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "IQIM" } ] }, "primary_object": { "basename": "2206.10076.pdf", "url": "https://authors.library.caltech.edu/records/18j3d-jg202/files/2206.10076.pdf" }, "pub_year": "2023", "author_list": "Ferreira, Vinicius S.; Kim, Gihwan; et el." }, { "id": "https://authors.library.caltech.edu/records/0rpkw-prb10", "eprint_id": 120114, "eprint_status": "archive", "datestamp": "2023-08-20 16:41:05", "lastmod": "2023-10-25 16:53:02", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chiappina-Piero", "name": { "family": "Chiappina", "given": "Piero" } }, { "id": "Banker-Jash", "name": { "family": "Banker", "given": "Jash" }, "orcid": "0000-0002-2130-0825" }, { "id": "Meesala-Srujan", "name": { "family": "Meesala", "given": "Srujan" } }, { "id": "Lake-David-P", "name": { "family": "Lake", "given": "David" }, "orcid": "0000-0002-0218-3555" }, { "id": "Wood-Steven", "name": { "family": "Wood", "given": "Steven" } }, { "id": "Painter-O", "name": { "family": "Painter", "given": "Oskar" }, "orcid": "0000-0002-1581-9209" } ] }, "title": "Design of an ultra-low mode volume piezo-optomechanical quantum transducer", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0)\n\nSubmitted - 2303.03664.pdf
", "abstract": "Coherent transduction of quantum states from the microwave to the optical domain can play a key role in quantum networking and distributed quantum computing. We present the design of a piezo-optomechanical device formed in a hybrid lithium niobate on silicon platform, that is suitable for microwave-to-optical quantum transduction. Our design is based on acoustic hybridization of an ultra-low mode volume piezoacoustic cavity with an optomechanical crystal cavity. The strong piezoelectric nature of lithium niobate allows us to mediate transduction via an acoustic mode which only minimally interacts with the lithium niobate, and is predominantly silicon-like, with very low electrical and acoustic loss. We estimate that this transducer can realize an intrinsic conversion efficiency of up to 35% with <0.5 added noise quanta when resonantly coupled to a superconducting transmon qubit and operated in pulsed mode at 10 kHz repetition rate. The performance improvement gained in such hybrid lithium niobate-silicon transducers make them suitable for heralded entanglement of qubits between superconducting quantum processors connected by optical fiber links.", "date": "2023-03-16", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20230316-224542308", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230316-224542308", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" }, { "id": "AWS-Center-for-Quantum-Computing" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "primary_object": { "basename": "2303.03664.pdf", "url": "https://authors.library.caltech.edu/records/0rpkw-prb10/files/2303.03664.pdf" }, "pub_year": "2023", "author_list": "Chiappina, Piero; Banker, Jash; et el." }, { "id": "https://authors.library.caltech.edu/records/18pxx-t5091", "eprint_id": 118568, "eprint_status": "archive", "datestamp": "2023-08-20 08:35:27", "lastmod": "2023-10-24 23:24:30", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lewis-Laura", "name": { "family": "Lewis", "given": "Laura" } }, { "id": "Zhu-Daiwei", "name": { "family": "Zhu", "given": "Daiwei" }, "orcid": "0000-0003-0019-256X" }, { "id": "Gheorghiu-Alexandru", "name": { "family": "Gheorghiu", "given": "Alexandru" }, "orcid": "0000-0001-6225-7168" }, { "id": "Noel-Crystal", "name": { "family": "Noel", "given": "Crystal" }, "orcid": "0000-0002-2977-2747" }, { "id": "Katz-Or", "name": { "family": "Katz", "given": "Or" }, "orcid": "0000-0001-7634-1993" }, { "id": "Harraz-Bahaa", "name": { "family": "Harraz", "given": "Bahaa" } }, { "id": "Wang-Qingfeng", "name": { "family": "Wang", "given": "Qingfeng" } }, { "id": "Risinger-Andrew", "name": { "family": "Risinger", "given": "Andrew" }, "orcid": "0000-0002-9770-5175" }, { "id": "Feng-Lei", "name": { "family": "Feng", "given": "Lei" }, "orcid": "0000-0001-8102-3420" }, { "id": "Biswas-Debopriyo", "name": { "family": "Biswas", "given": "Debopriyo" }, "orcid": "0000-0003-2720-5279" }, { "id": "Egan-Laird", "name": { "family": "Egan", "given": "Laird" }, "orcid": "0000-0003-2405-9106" }, { "id": "Vidick-T", "name": { "family": "Vidick", "given": "Thomas" }, "orcid": "0000-0002-6405-365X" }, { "id": "Cetina-Marko", "name": { "family": "Cetina", "given": "Marko" }, "orcid": "0000-0003-1942-9977" }, { "id": "Monroe-Christopher", "name": { "family": "Monroe", "given": "Christopher" }, "orcid": "0000-0003-0551-3713" } ] }, "title": "Experimental Implementation of an Efficient Test of Quantumness", "ispublished": "unpub", "full_text_status": "public", "note": "This work is supported by AFOSR YIP award number FA9550-16-1-0495, a Simons Foundation (828076, TV) grant, MURI Grant FA9550-18-1-0161, the NSF QLCI program (OMA-2016245), the IQIM, an NSF Physics Frontiers Center (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028), Dr. Max R\u00f6ssler, the Walter Haefner Foundation, the ETH Z\u00fcrich Foundation, a Caltech Summer Undegraduate Research Fellowship (SURF), the ARO through the IARPA LogiQ program, the NSF STAQ program, the U.S. Department of Energy Quantum Systems Accelerator (QSA) program, the AFOSR MURI on Scalable Certification of Quantum Computing Devices and Networks, the AFOSR MURI on Dissipation Engineering in Open Quantum Systems, and the ARO MURI on Modular Quantum Circuits. \n\nCompeting Interests: C.M. is Chief Scientist for IonQ, Inc. and has a personal financial interest in the company.", "abstract": "A test of quantumness is a protocol where a classical user issues challenges to a quantum device to determine if it exhibits non-classical behavior, under certain cryptographic assumptions. Recent attempts to implement such tests on current quantum computers rely on either interactive challenges with efficient verification, or non-interactive challenges with inefficient (exponential time) verification. In this paper, we execute an efficient non-interactive test of quantumness on an ion-trap quantum computer. Our results significantly exceed the bound for a classical device's success.", "date": "2022-12-21", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20221221-004807787", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221221-004807787", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0495" }, { "agency": "Simons Foundation", "grant_number": "828076" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0161" }, { "agency": "NSF", "grant_number": "OMA-2016245" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" }, { "agency": "Dr. Max R\u00f6ssler" }, { "agency": "Walter Haefner Foundation" }, { "agency": "ETH Z\u00fcrich Foundation" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" }, { "agency": "Army Research Office (ARO)" }, { "agency": "Department of Energy (DOE)" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2209.14316", "pub_year": "2022", "author_list": "Lewis, Laura; Zhu, Daiwei; et el." }, { "id": "https://authors.library.caltech.edu/records/4d0yn-88k35", "eprint_id": 118520, "eprint_status": "archive", "datestamp": "2023-08-20 07:32:53", "lastmod": "2023-10-24 23:23:33", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mahadev-Urmila", "name": { "family": "Mahadev", "given": "Urmila" } }, { "id": "Vazirani-Umesh-V", "name": { "family": "Vazirani", "given": "Umesh" } }, { "id": "Vidick-T", "name": { "family": "Vidick", "given": "Thomas" }, "orcid": "0000-0002-6405-365X" } ] }, "title": "Efficient Certifiable Randomness from a Single Quantum Device", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nT.V. is supported by AFOSR YIP award number FA9550-16-1-0495, a grant from the Simons Foundation (828076, TV), MURI Grant FA9550-18-1-0161, the NSF QLCI program through grant number OMA-2016245 and the IQIM, an NSF Physics Frontiers Center (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028). U.M. is supported by an NSF CAREER grant (2048204). U.V. is supported by Vannevar Bush faculty fellowship N00014-17-1-3025, MURI Grant FA9550-18-1-0161, and DOE NQISRC Quantum Systems Accelerator grant FP00010905.\n\nSubmitted - 2204.11353.pdf
", "abstract": "Brakerski et. al [BCM+18] introduced the model of cryptographic testing of a single untrusted quantum device and gave a protocol for certifiable randomness generation. We use the leakage resilience properties of the Learning With Errors problem to address a key issue left open in previous work - the rate of generation of randomness. Our new protocol can certify \u03a9(n) fresh bits of randomness in constant rounds, where n is a parameter of the protocol and the total communication is O(n), thus achieving a nearly optimal rate. The proof that the output is statistically random is conceptually simple and technically elementary.", "date": "2022-12-21", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20221220-222320267", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221220-222320267", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0495" }, { "agency": "Simons Foundation", "grant_number": "828076" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0161" }, { "agency": "NSF", "grant_number": "OMA-2016245" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" }, { "agency": "NSF", "grant_number": "CCF-2048204" }, { "agency": "Vannever Bush Faculty Fellowship", "grant_number": "N00014-17-1-3025" }, { "agency": "Department of Energy (DOE)", "grant_number": "FP00010905" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2204.11353", "primary_object": { "basename": "2204.11353.pdf", "url": "https://authors.library.caltech.edu/records/4d0yn-88k35/files/2204.11353.pdf" }, "pub_year": "2022", "author_list": "Mahadev, Urmila; Vazirani, Umesh; et el." }, { "id": "https://authors.library.caltech.edu/records/z26mx-8sb85", "eprint_id": 118567, "eprint_status": "archive", "datestamp": "2023-08-20 08:05:19", "lastmod": "2023-10-24 23:24:28", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bartusek-James", "name": { "family": "Bartusek", "given": "James" } }, { "id": "Kalai-Yael-Tauman", "name": { "family": "Kalai", "given": "Yael Tauman" } }, { "id": "Lombardi-Alex", "name": { "family": "Lombardi", "given": "Alex" } }, { "id": "Ma-Fermi", "name": { "family": "Ma", "given": "Fermi" } }, { "id": "Malavolta-Giulio", "name": { "family": "Malavolta", "given": "Giulio" } }, { "id": "Vaikuntanathan-Vinod", "name": { "family": "Vaikuntanathan", "given": "Vinod" } }, { "id": "Vidick-T", "name": { "family": "Vidick", "given": "Thomas" }, "orcid": "0000-0002-6405-365X" }, { "id": "Yang-Lisa", "name": { "family": "Yang", "given": "Lisa" } } ] }, "title": "Succinct Classical Verification of Quantum Computation", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) \n\nAL is supported in part by a Charles M. Vest fellowship. GM is partially supported by the German Federal Ministry of Education and Research BMBF (grant 16K15K042, project 6GEM). TV is supported by AFOSR YIP award number FA9550-16-1-0495, a grant from the Simons Foundation (828076, TV), MURI Grant FA9550-18-1-0161, the NSF QLCI program through grant number OMA-2016245 and the IQIM, an NSF Physics Frontiers Center (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028). AL, VV, and LY are supported in part by DARPA under Agreement No. HR00112020023, a grant from MIT-IBM Watson AI, a grant from Analog Devices, a Microsoft Trustworthy AI grant and the Thornton Family Faculty Research Innovation Fellowship. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the United States Government or DARPA. LY was supported in part by an NSF graduate research fellowship.\n\nSubmitted - 2206.14929.pdf
", "abstract": "We construct a classically verifiable succinct interactive argument for quantum computation (BQP) with communication complexity and verifier runtime that are poly-logarithmic in the runtime of the BQP computation (and polynomial in the security parameter). Our protocol is secure assuming the post-quantum security of indistinguishability obfuscation (iO) and Learning with Errors (LWE). This is the first succinct argument for quantum computation in the plain model; prior work (Chia-Chung-Yamakawa, TCC '20) requires both a long common reference string and non-black-box use of a hash function modeled as a random oracle.\nAt a technical level, we revisit the framework for constructing classically verifiable quantum computation (Mahadev, FOCS '18). We give a self-contained, modular proof of security for Mahadev's protocol, which we believe is of independent interest. Our proof readily generalizes to a setting in which the verifier's first message (which consists of many public keys) is compressed. Next, we formalize this notion of compressed public keys; we view the object as a generalization of constrained/programmable PRFs and instantiate it based on indistinguishability obfuscation.\nFinally, we compile the above protocol into a fully succinct argument using a (sufficiently composable) succinct argument of knowledge for NP. Using our framework, we achieve several additional results, including\n- Succinct arguments for QMA (given multiple copies of the witness),\n- Succinct non-interactive arguments for BQP (or QMA) in the quantum random oracle model, and\n- Succinct batch arguments for BQP (or QMA) assuming post-quantum LWE (without iO).", "date": "2022-12-21", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20221221-004803338", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221221-004803338", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Academy of Engineering" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)", "grant_number": "16K15K042" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0495" }, { "agency": "Simons Foundation", "grant_number": "828076" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0161" }, { "agency": "NSF", "grant_number": "OMA-2016245" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "HR00112020023" }, { "agency": "MIT-IBM Watson AI Lab" }, { "agency": "Analog Devices" }, { "agency": "Microsoft Research" }, { "agency": "Massachusetts Institute of Technology (MIT)" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2206.14929", "primary_object": { "basename": "2206.14929.pdf", "url": "https://authors.library.caltech.edu/records/z26mx-8sb85/files/2206.14929.pdf" }, "pub_year": "2022", "author_list": "Bartusek, James; Kalai, Yael Tauman; et el." }, { "id": "https://authors.library.caltech.edu/records/qy2mc-7gp10", "eprint_id": 121379, "eprint_status": "archive", "datestamp": "2023-08-20 08:41:02", "lastmod": "2023-10-20 15:26:35", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhao-Han", "name": { "family": "Zhao", "given": "Han" } }, { "id": "Bozkurt-Alk\u0131m-B", "name": { "family": "Bozkurt", "given": "Alk\u0131m" }, "orcid": "0000-0003-0633-8902" }, { "id": "Mirhosseini-M", "name": { "family": "Mirhosseini", "given": "Mohammad" }, "orcid": "0000-0002-9084-6880" } ] }, "title": "Electro-optic transduction in silicon via GHz-frequency nanomechanics", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nWe acknowledge Peter Day at NASA Jet Propulsion Laboratory for the deposition of TiN films.\n\nSubmitted - 2210.13549.pdf
", "abstract": "Interfacing electronics with optical fiber networks is key to the long-distance transfer of classical and quantum information. Piezo-optomechanical transducers enable such interfaces by using GHz-frequency acoustic vibrations as mediators for converting microwave photons to optical photons via the combination of optomechanical and piezoelectric interactions. However, despite successful demonstrations, efficient piezo-optomechanical transduction remains out of reach due to the challenges associated with hybrid material integration and increased loss from piezoelectric materials when operating in the quantum regime. Here, we demonstrate an alternative approach in which we actuate 5-GHz phonons in a conventional silicon-on-insulator platform. In our experiment, microwave photons resonantly drive a phononic crystal oscillator via the electrostatic force realized in a charge-biased narrow-gap capacitor. The mechanical vibrations are subsequently transferred via a phonon waveguide to an optomechanical cavity, where they transform into optical photons in the sideband of a pump laser field. Operating at room temperature and atmospheric pressure, we measure a microwave-to-optical photon conversion efficiency of 1.8 \u00d7 10\u207b\u2077 in a 3.3 MHz bandwidth, and demonstrate efficient phase modulation with a half-wave voltage of V_\u03c0 = 750 mV. Our results mark a stepping stone towards quantum transduction with integrated devices made from crystalline silicon, which promise efficient high-bandwidth operation, and integration with superconducting qubits. Additionally, the lack of need for piezoelectricity or other intrinsic nonlinearities makes our approach adaptable to a wide range of materials for potential applications beyond quantum technologies.", "date": "2022-10-24", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20230512-186474000.2", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230512-186474000.2", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" } ] }, "primary_object": { "basename": "2210.13549.pdf", "url": "https://authors.library.caltech.edu/records/qy2mc-7gp10/files/2210.13549.pdf" }, "pub_year": "2022", "author_list": "Zhao, Han; Bozkurt, Alk\u0131m; et el." }, { "id": "https://authors.library.caltech.edu/records/zkt65-24m51", "eprint_id": 116310, "eprint_status": "archive", "datestamp": "2023-08-20 08:14:55", "lastmod": "2023-10-24 21:04:56", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Esin-Iliya", "name": { "family": "Esin", "given": "Iliya" }, "orcid": "0000-0003-2959-0617" }, { "id": "Esterlis-Ilya", "name": { "family": "Esterlis", "given": "Ilya" }, "orcid": "0000-0003-4775-9105" }, { "id": "Demler-Eugene-A", "name": { "family": "Demler", "given": "Eugene" }, "orcid": "0000-0002-2499-632X" }, { "id": "Refael-G", "name": { "family": "Refael", "given": "Gil" } } ] }, "title": "Generating coherent phonon waves in narrow-band materials: a twisted bilayer graphene phaser", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nWe thank Kenneth Burch, Jerome Faist, Mohammad Hafezi, Atac Imamoglu, Cyprian Lewandowski, Marios Michael, Leo Radzihovsky, and Christopher Yang for valuable discussions. G. Refael and I. Esin are grateful for support from the Simons Foundation and the Institute of Quantum Information and Matter, as well as support from the NSF DMR grant number 1839271. E. Demler and I. Esterlis acknowledge support from the ARO grant \"Control of Many-Body States Using Strong Coherent Light-Matter Coupling in Terahertz Cavities\". This work is supported by ARO MURI Grant No. W911NF-16-1-0361, and was performed in part at Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611.\n\nSubmitted - 2207.11245.pdf
", "abstract": "Twisted bilayer graphene (TBG) exhibits extremely low Fermi velocities for electrons, with the speed of sound surpassing the Fermi velocity. This regime enables the use of TBG for amplifying vibrational waves of the lattice through stimulated emission, following the same principles of operation of free-electron lasers. Our work proposes a lasing mechanism relying on the slow-electron bands to produce a coherent beam of acoustic phonons. We propose a device based on undulated electrons in TBG, which we dub the phaser. The device generates phonon beams in a terahertz (THz) frequency range, which can then be used to produce THz electromagnetic radiation. The ability to generate coherent phonons in solids breaks new ground in controlling quantum memories, probing quantum states, realizing non-equilibrium phases of matter, and designing new types of THz optical devices.", "date": "2022-08-16", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220816-183030641", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220816-183030641", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Simons Foundation" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "DMR-1839271" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-16-1-0361" }, { "agency": "NSF", "grant_number": "PHY-1607611" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2207.11245", "primary_object": { "basename": "2207.11245.pdf", "url": "https://authors.library.caltech.edu/records/zkt65-24m51/files/2207.11245.pdf" }, "pub_year": "2022", "author_list": "Esin, Iliya; Esterlis, Ilya; et el." }, { "id": "https://authors.library.caltech.edu/records/5a1tw-xf975", "eprint_id": 116315, "eprint_status": "archive", "datestamp": "2023-08-20 08:14:29", "lastmod": "2023-10-24 21:05:06", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tang-Yuchen", "name": { "family": "Tang", "given": "Yuchen" } }, { "id": "Knapp-Christina", "name": { "family": "Knapp", "given": "Christina" }, "orcid": "0000-0002-5982-8107" }, { "id": "Alicea-J", "name": { "family": "Alicea", "given": "Jason" }, "orcid": "0000-0001-9979-3423" } ] }, "title": "Vortex-enabled Andreev processes in quantum Hall-superconductor hybrids", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nThis work was supported by the Army Research Office under Grant Award W911NF-17-1-0323; the Caltech Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation through Grant GBMF1250; and the Walter Burke Institute for Theoretical Physics at Caltech.\n\nSubmitted - 2207.10687.pdf
", "abstract": "Quantum Hall-superconductor heterostructures provide possible platforms for intrinsically fault-tolerant quantum computing. Motivated by several recent experiments that successfully integrated these phases, we investigate transport through a proximitized integer quantum Hall edge--paying particular attention to the impact of vortices in the superconductor. By examining the downstream conductance, we identify regimes in which sub-gap vortex levels mediate Andreev processes that would otherwise be frozen out in a vortex-free setup. Moreover, we show that at finite temperature, and in the limit of a large number of vortices, the downstream conductance can average to zero, indicating that the superconductor effectively behaves like a normal contact. Our results highlight the importance of considering vortices when using transport measurements to study superconducting correlations in quantum Hall-superconductor hybrids.", "date": "2022-08-16", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220816-192424755", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220816-192424755", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-17-1-0323" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF Physics Frontiers Center" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1250" }, { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.2207.10687", "primary_object": { "basename": "2207.10687.pdf", "url": "https://authors.library.caltech.edu/records/5a1tw-xf975/files/2207.10687.pdf" }, "pub_year": "2022", "author_list": "Tang, Yuchen; Knapp, Christina; et el." }, { "id": "https://authors.library.caltech.edu/records/7btgy-p9d44", "eprint_id": 116308, "eprint_status": "archive", "datestamp": "2023-08-20 08:13:09", "lastmod": "2023-10-24 21:04:54", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lewandowski-Cyprian", "name": { "family": "Lewandowski", "given": "Cyprian" }, "orcid": "0000-0002-6944-9805" }, { "id": "Lantagne-Hurtubise-\u00c9tienne", "name": { "family": "Lantagne-Hurtubise", "given": "\u00c9tienne" }, "orcid": "0000-0003-0417-6452" }, { "id": "Thomson-Alex", "name": { "family": "Thomson", "given": "Alex" }, "orcid": "0000-0002-9938-5048" }, { "id": "Nadj-Perge-S", "name": { "family": "Nadj-Perge", "given": "Stevan" }, "orcid": "0000-0002-2394-9070" }, { "id": "Alicea-J", "name": { "family": "Alicea", "given": "Jason" }, "orcid": "0000-0001-9979-3423" } ] }, "title": "Andreev reflection spectroscopy in strongly paired superconductors", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nWe thank Mohit Randeria, Hyunjin Kim, Micha l Papaj, and Kevin Nuckolls for insightful discussions. This work was supported by the Gordon and Betty Moore Foundation's EPiQS Initiative, Grant GBMF8682 (C.L. and \u00c9.L.-H.); the Army Research Office under Grant Award W911NF-17-1-0323; the Caltech Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation through Grant GBMF1250; and the Walter Burke Institute for Theoretical Physics at Caltech.\n\nSubmitted - 2207.09494.pdf
", "abstract": "Motivated by recent experiments on low-carrier-density superconductors, including twisted multilayer graphene, we study signatures of the BCS to BEC evolution in Andreev reflection spectroscopy. We establish that in a standard quantum point contact geometry, Andreev reflection in a BEC superconductor is unable to mediate a zero-bias conductance beyond e\u00b2/h per lead channel. This bound is shown to result from a duality that links the sub-gap conductance of BCS and BEC superconductors. We then demonstrate that sharp signatures of BEC superconductivity, including perfect Andreev reflection, can be recovered by tunneling through a suitably designed potential well. We propose various tunneling spectroscopy setups to experimentally probe this recovery.", "date": "2022-08-16", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220816-183023896", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220816-183023896", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF8682" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-17-1-0323" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1250" }, { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.2207.09494", "primary_object": { "basename": "2207.09494.pdf", "url": "https://authors.library.caltech.edu/records/7btgy-p9d44/files/2207.09494.pdf" }, "pub_year": "2022", "author_list": "Lewandowski, Cyprian; Lantagne-Hurtubise, \u00c9tienne; et el." }, { "id": "https://authors.library.caltech.edu/records/tkxjj-eng27", "eprint_id": 116139, "eprint_status": "archive", "datestamp": "2023-08-20 07:39:01", "lastmod": "2023-10-24 20:59:51", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Berta-Mario", "name": { "family": "Berta", "given": "Mario" }, "orcid": "0000-0002-0428-3429" }, { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" }, { "id": "Gour-Gilad", "name": { "family": "Gour", "given": "Gilad" }, "orcid": "0000-0002-4892-4072" }, { "id": "Lami-Ludovico", "name": { "family": "Lami", "given": "Ludovico" }, "orcid": "0000-0003-3290-3557" }, { "id": "Plenio-Martin-B", "name": { "family": "Plenio", "given": "Martin B." }, "orcid": "0000-0003-4238-8843" }, { "id": "Regula-Bartosz", "name": { "family": "Regula", "given": "Bartosz" }, "orcid": "0000-0001-7225-071X" }, { "id": "Tomamichel-Marco", "name": { "family": "Tomamichel", "given": "Marco" }, "orcid": "0000-0001-5410-3329" } ] }, "title": "On a gap in the proof of the generalised quantum Stein's lemma and its consequences for the reversibility of quantum resources", "ispublished": "unpub", "full_text_status": "public", "note": "LL is financially supported by the Alexander von Humboldt Foundation. GG is supported by Natural Sciences and Engineering Research Council of Canada (NSERC). BR is supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI Grant No. 21F21015 and the JSPS Postdoctoral Fellowship for Research in Japan. MT is funded by the National Research Foundation, Prime Minister's Office, Singapore and the Ministry of Education, Singapore under the Research Centres of Excellence programme, as well as startup grants (R-263-000-E32-133 and R-263-000-E32-731).\n\nSubmitted - 2205.02813.pdf
", "abstract": "We show that the proof of the generalised quantum Stein's lemma [Brand\u00e3o & Plenio, Commun. Math. Phys. 295, 791 (2010)] is not correct due to a gap in the argument leading to Lemma III.9. Hence, the main achievability result of Brand\u00e3o & Plenio is not known to hold. This puts into question a number of established results in the literature, in particular the reversibility of quantum entanglement [Brand\u00e3o & Plenio, Commun. Math. Phys. 295, 829 (2010); Nat. Phys. 4, 873 (2008)] and of general quantum resources [Brand\u00e3o & Gour, Phys. Rev. Lett. 115, 070503 (2015)] under asymptotically resource non-generating operations. We discuss potential ways to recover variants of the newly unsettled results using other approaches.", "date": "2022-08-09", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220804-201336824", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220804-201336824", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Alexander von Humboldt Foundation" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Japan Society for the Promotion of Science (JSPS)", "grant_number": "21F21015" }, { "agency": "National Research Foundation (Singapore)" }, { "agency": "Ministry of Education (Singapore)" }, { "agency": "National University of Singapore", "grant_number": "R-263-000-E32-133" }, { "agency": "National University of Singapore", "grant_number": "R-263-000-E32-731" } ] }, "local_group": { "items": [ { "id": "AWS-Center-for-Quantum-Computing" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2205.02813", "primary_object": { "basename": "2205.02813.pdf", "url": "https://authors.library.caltech.edu/records/tkxjj-eng27/files/2205.02813.pdf" }, "pub_year": "2022", "author_list": "Berta, Mario; Brand\u00e3o, Fernando G. S. L.; et el." }, { "id": "https://authors.library.caltech.edu/records/g5ns4-9rc08", "eprint_id": 115408, "eprint_status": "archive", "datestamp": "2023-08-20 07:45:09", "lastmod": "2023-10-24 16:30:03", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yu-Phelan", "name": { "family": "Yu", "given": "Phelan" }, "orcid": "0000-0002-3715-9133" }, { "id": "Lopez-Adrian-A", "name": { "family": "Lopez", "given": "Adrian" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Hutzler-N-R", "name": { "family": "Hutzler", "given": "Nicholas R." }, "orcid": "0000-0002-5203-3635" } ] }, "title": "Multivalent optical cycling centers in polyatomic molecules", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Benjamin Augenbraun, Lan Cheng, Arian Jadbabaie, Anna Krylov, Nick Pilgram, and Pawe\u0142 W\u00f3jcik for insightful discussions and feedback. P. Y. acknowledges support from the Eddleman Graduate Fellowship through the Institute for Quantum Information and Matter (IQIM), the Gordon and Betty Moore Foundation (7947), and the Alfred P. Sloan Foundation (G2019-12502). A. L. acknowledges support from the C. S. Shastry Prize and the Caltech Associates SURF Fellowship. W. A. G. was supported by the Ferkel Chair. N. R. H. acknowledges support from the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), under Award No. DE-SC0019245. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology\n\nSubmitted - 2205.11860.pdf
", "abstract": "Optical control of polyatomic molecules promises new opportunities in precision metrology, fundamental chemistry, quantum information, and many-body science. Contemporary experimental and theoretical efforts have mostly focused on cycling photons via excitation of a single electron localized to an alkaline earth (group 2)-like metal center. In this manuscript, we consider pathways towards optical cycling in polyatomic molecules with multi-electron degrees of freedom, which arise from two or more cycling electrons localized to p-block post-transition metal and metalloid (group 13, 14, and 15) centers. We characterize the electronic structure and rovibrational branching of several prototypical candidates using ab initio quantum chemical methods. Despite increased internal complexity and challenging design parameters, we find several molecules possessing quasi-closed photon cycling schemes with highly diagonal, visible and near-infrared transitions. Furthermore, we identify new heuristics for engineering optically controllable and laser-coolable polyatomic molecules with multi-electron cycling centers. Our results help elucidate the interplay between hybridization, repulsion, and ionicity in optically active species and provide a first step towards using polyatomic molecules with complex electronic structure as a resource for quantum science and measurement.", "date": "2022-07-08", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220707-204114065", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220707-204114065", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "7947" }, { "agency": "Alfred P. Sloan Foundation", "grant_number": "G2019-12502" }, { "agency": "C. S. Shastry Prize" }, { "agency": "Caltech Associates" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" }, { "agency": "Charles and Mary Ferkel Professor of Chemistry, Materials Science, and Applied Physics" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019245" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.48550/arXiv.arXiv.2205.11860", "primary_object": { "basename": "2205.11860.pdf", "url": "https://authors.library.caltech.edu/records/g5ns4-9rc08/files/2205.11860.pdf" }, "pub_year": "2022", "author_list": "Yu, Phelan; Lopez, Adrian; et el." }, { "id": "https://authors.library.caltech.edu/records/2kzsv-h7m65", "eprint_id": 115409, "eprint_status": "archive", "datestamp": "2023-08-20 07:53:23", "lastmod": "2023-10-24 16:30:07", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nathan-Frederik", "name": { "family": "Nathan", "given": "Frederik" }, "orcid": "0000-0001-9700-0231" }, { "id": "Rudner-Mark-S", "name": { "family": "Rudner", "given": "Mark S." }, "orcid": "0000-0002-5150-6234" } ] }, "title": "High accuracy steady states obtained from the Universal Lindblad Equation", "ispublished": "unpub", "full_text_status": "public", "note": "We would like to thank A. Dhar, G. Kirsanskas, M. Kulkarni, M. Leijnse, A. Purkayastha, and D. Tupkary for helpful and clarifying discussions and for pointing out the limitations of the ULE (and Lindblad equations in general), which we address in the present work. F.N. and M.R. gratefully acknowledge the support of Villum Foundation, the European Research Council (ERC) under the European Union Horizon 2020 Research and Innovation Programme (Grant Agreement No. 678862), and CRC 183 of the Deutsche Forschungsgemeinschaft. F.N. acknowledges support from the U.S. Department of Energy, Office of Science, Basic Energy Sciences under award DE-SC0019166 and the Simons Foundation under award 623768.\n\nSubmitted - 2206.02917.pdf
", "abstract": "We show that the universal Lindblad equation (ULE) captures steady-state expectation values of observables up to rigorously bounded corrections that scale linearly with the system-bath coupling, \u0393. We moreover identify a simple quasilocal transformation, whose application guarantees a relative deviation generically scaling to zero with \u0393, even for observables such as currents whose steady-state values themselves vanish in the weak coupling limit. This result provides a solution to recently identified limitations on the accuracy of Lindblad-form master equations, which imply significan't relative errors for observables whose steady-state values vanish with \u0393, while most generic observables are otherwise captured faithfully. The transformation allows for high-fidelity computation of sensitive observables while retaining the stability and physicality of a Lindblad-form master equation.", "date": "2022-07-08", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220707-204116791", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220707-204116791", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Villum Foundation" }, { "agency": "European Research Council (ERC)", "grant_number": "678862" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "CRC 183" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019166" }, { "agency": "Simons Foundation", "grant_number": "623768" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.arXiv.2206.02917", "primary_object": { "basename": "2206.02917.pdf", "url": "https://authors.library.caltech.edu/records/2kzsv-h7m65/files/2206.02917.pdf" }, "pub_year": "2022", "author_list": "Nathan, Frederik and Rudner, Mark S." }, { "id": "https://authors.library.caltech.edu/records/depm8-mc385", "eprint_id": 115286, "eprint_status": "archive", "datestamp": "2023-08-20 08:03:19", "lastmod": "2023-10-24 15:30:38", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Xueyue", "name": { "family": "Zhang", "given": "Xueyue" }, "orcid": "0000-0001-8994-0629" }, { "id": "Kim-Eunjong", "name": { "family": "Kim", "given": "Eunjong" }, "orcid": "0000-0003-4879-8819" }, { "id": "Mark-Daniel-K", "name": { "family": "Mark", "given": "Daniel K." }, "orcid": "0000-0002-5017-5218" }, { "id": "Choi-Soonwon", "name": { "family": "Choi", "given": "Soonwon" }, "orcid": "0000-0002-1247-062X" }, { "id": "Painter-O", "name": { "family": "Painter", "given": "Oskar" }, "orcid": "0000-0002-1581-9209" } ] }, "title": "A scalable superconducting quantum simulator with long-range\n connectivity based on a photonic bandgap metamaterial", "ispublished": "unpub", "full_text_status": "public", "note": "The authors thank Alexey Gorshkov, Alejandro\nGonzalez-Tudela, Darrick Chang, Olexei Motrunich,\nRuichao Ma, Fernando Brandao, Gil Refael, and Zhaoyi\nZheng for helpful discussions. We appreciate MIT Lincoln Laboratories for the provision of traveling-wave\nparametric amplifiers used for both spectroscopic and\ntime-domain measurements in this work, and the AWS\nCenter for Quantum Computing for the Eccosorb filters installed in the cryogenic setup for infrared filtering.\nWe also thank the Quantum Machines team for technical support and discussions on the Quantum Orchestration Platform. This work was supported by the AFOSR\nQuantum Photonic Matter MURI (grant FA9550-16-1-0323), the DOE-BES Quantum Information Science Program (grant DE-SC0020152), the Institute for Quantum\nInformation and Matter, an NSF Physics Frontiers Center (grant PHY-1125565) with support of the Gordon\nand Betty Moore Foundation, the Kavli Nanoscience Institute at Caltech, and the AWS Center for Quantum\nComputing. D. K. M. acknowledges support from the\nNSF QLCI program (2016245) and the DOE Quantum\nSystems Accelerator Center (contract no. 7568717).\n\nSubmitted - 2206.12803.pdf
", "abstract": "Synthesis of many-body quantum systems in the laboratory can provide further\ninsight into the emergent behavior of quantum materials. While the majority of\nengineerable many-body systems, or quantum simulators, consist of particles on\na lattice with local interactions, quantum systems featuring long-range\ninteractions are particularly difficult to model and interesting to study due\nto the rapid spatio-temporal growth of entanglement in such systems. Here we\npresent a scalable quantum simulator architecture based on superconducting\ntransmon qubits on a lattice, with interactions mediated by the exchange of\nphotons via a metamaterial waveguide quantum bus. The metamaterial waveguide\nenables extensible scaling of the system and multiplexed qubit read-out, while\nsimultaneously protecting the qubits from radiative decay. As an initial\ndemonstration of this platform, we realize a 10-qubit simulator of the\none-dimensional Bose-Hubbard model, with in situ tunability of both the hopping\nrange and the on-site interaction. We characterize the Hamiltonian of the\nsystem using a measurement-efficient protocol based on quantum many-body chaos,\nuncovering the remnant phase of Bloch waves of the metamaterial bus in the\nlong-range hopping terms. We further study the many-body quench dynamics of the\nsystem, revealing through global bit-string statistics the predicted crossover\nfrom integrability to ergodicity as the hopping range is extended beyond\nnearest-neighbor. Looking forward, the metamaterial quantum bus may be extended\nto a two-dimensional lattice of qubits, and used to generate other spin-like\nlattice interactions or tailored lattice connectivity, expanding the accessible\nHamiltonians for analog quantum simulation using superconducting quantum\ncircuits.", "date": "2022-06-29", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220628-234305742", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220628-234305742", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0323" }, { "agency": "DOE", "grant_number": "DE-SC0020152" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "NSF", "grant_number": "OMA-2016245" }, { "agency": "Quantum Systems Accelerator", "grant_number": "7568717" } ] }, "local_group": { "items": [ { "id": "AWS-Center-for-Quantum-Computing" }, { "id": "IQIM" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.48550/arXiv.2206.12803", "primary_object": { "basename": "2206.12803.pdf", "url": "https://authors.library.caltech.edu/records/depm8-mc385/files/2206.12803.pdf" }, "pub_year": "2022", "author_list": "Zhang, Xueyue; Kim, Eunjong; et el." }, { "id": "https://authors.library.caltech.edu/records/m8brt-1ce36", "eprint_id": 114893, "eprint_status": "archive", "datestamp": "2023-08-20 07:15:00", "lastmod": "2023-10-24 15:14:51", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Taranto-William", "name": { "family": "Taranto", "given": "William" } }, { "id": "Lederer-Samuel", "name": { "family": "Lederer", "given": "Samuel" }, "orcid": "0000-0002-7443-3859" }, { "id": "Choi-Youngjoon", "name": { "family": "Choi", "given": "Youngjoon" } }, { "id": "Izmailov-Pavel", "name": { "family": "Izmailov", "given": "Pavel" } }, { "id": "Wilson-Andrew-Gordon", "name": { "family": "Wilson", "given": "Andrew Gordon" }, "orcid": "0000-0002-2011-3315" }, { "id": "Nadj-Perge-S", "name": { "family": "Nadj-Perge", "given": "Stevan" }, "orcid": "0000-0002-2394-9070" }, { "id": "Kum-Eun-Ah", "name": { "family": "Kim", "given": "Eun-Ah" } } ] }, "title": "Unsupervised learning of two-component nematicity from STM data on magic angle bilayer graphene", "ispublished": "unpub", "full_text_status": "public", "note": "SL, PI , AGW, and E-AK acknowledge NSF, Institutes for Data-Intensive Research in Science and Engineering \u2013 Frameworks (OAC-19347141934714). SL is supported by the U.S. Department of Energy, Office of Science, National Quantum Information Science Research Centers, Quantum Systems Accelerator (QSA). S.N-P. acknowledges support from the NSF (grant DMR-2005129) and the Sloan Foundation (grant FG-2020-13716).\n\nSubmitted - 2203.04449.pdf
", "abstract": "Moir\u00e9 materials such as magic angle twisted bilayer graphene (MATBG) exhibit remarkable phenomenology, but present significant challenges for certain experimental methods, particularly scanning probes such as scanning tunneling microscopy (STM). Typical STM studies that can image tens of thousands of atomic unit cells can image roughly ten moir\u00e9 cells, making data analysis statistically fraught. Here, we propose a method to mitigate this problem by aggregating STM conductance data from several bias voltages, and then using the unsupervised machine learning method of gaussian mixture model clustering to draw maximal insight from the resulting dataset. We apply this method, using as input coarse-grained bond variables respecting the point group symmetry, to investigate nematic ordering tendencies in MATBG for both charge neutral and hole-doped samples. For the charge-neutral dataset, the clustering reveals the surprising coexistence of multiple types of nematicity that are unrelated by symmetry, and therefore generically nondegenerate. By contrast, the clustering in the hole doped data is consistent with long range order of a single type. Beyond its value in analyzing nematicity in MATBG, our method has the potential to enhance understanding of symmetry breaking and its spatial variation in a variety of moir\u00e9 materials.", "date": "2022-05-31", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220524-180254587", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220524-180254587", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "OAC-1934714" }, { "agency": "Department of Energy (DOE)" }, { "agency": "NSF", "grant_number": "DMR-2005129" }, { "agency": "Alfred P. Sloan Foundation", "grant_number": "FG-2020-13716" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2203.04449", "primary_object": { "basename": "2203.04449.pdf", "url": "https://authors.library.caltech.edu/records/m8brt-1ce36/files/2203.04449.pdf" }, "pub_year": "2022", "author_list": "Taranto, William; Lederer, Samuel; et el." }, { "id": "https://authors.library.caltech.edu/records/rsb00-t1284", "eprint_id": 115410, "eprint_status": "archive", "datestamp": "2023-08-20 07:45:45", "lastmod": "2023-10-24 16:30:10", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Xinwei", "name": { "family": "Li", "given": "Xinwei" }, "orcid": "0000-0003-0555-2624" }, { "id": "Kono-Junichiro", "name": { "family": "Kono", "given": "Junichiro" }, "orcid": "0000-0002-4195-0577" }, { "id": "Si-Qimiao", "name": { "family": "Si", "given": "Qimiao" }, "orcid": "0000-0003-1357-2705" }, { "id": "Paschen-Silke", "name": { "family": "Paschen", "given": "Silke" }, "orcid": "0000-0002-3796-0713" } ] }, "title": "Is the optical conductivity of heavy fermion strange metals Planckian?", "ispublished": "unpub", "full_text_status": "public", "keywords": "strange metals, Planckian scattering, optical conductivity, Drude model, heavy fermion compounds, quantum criticality,\nnon-Fermi liquid, YbRh\u2082Si\u2082", "note": "We acknowledge fruitful discussion with Patrick Lee, Marc Scheffler, T. Senthil, Mathieu Taupin, and Eric van Heumen. \n\nXL acknowledges support from the Caltech Postdoctoral Prize Fellowship and the IQIM. JK acknowledges support from the Robert A. Welch Foundation through Grant No. C-1509. QS acknowledges support from the Air Force Office of Scientific Research under Grant No. FA9550-21-1-0356 and the Robert A. Welch Foundation under Grant No. C-1411. SP acknowledges funding from the European Union's Horizon 2020 Research and Innovation Programme under Grant Agreement no 824109 and from the Austrian Science Fund (FWF Grants 29296-N27 and I5868-N\u2013FOR 5249 - QUAST). SP and QS acknowledge the hospitality of the Aspen Center for Physics, which is supported by NSF grant No. PHY-1607611. \n\nAUTHOR CONTRIBUTIONS. XL performed the Drude analyses, SP conceived the work and wrote the paper, with input from XL, JK, and QS. All authors contributed to the discussion. \n\nThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.\n\nSubmitted - 2205.13382.pdf
", "abstract": "Strange metal behavior appears across a variety of condensed matter settings and beyond, and achieving a universal understanding is an exciting prospect. The beyond-Landau quantum criticality of Kondo destruction has had considerable success in describing the behavior of strange metal heavy fermion compounds, and there is some evidence that the associated partial localization-delocalization nature can be generalized to diverse materials classes. Other potential overarching principles at play are also being explored. An intriguing proposal is that Planckian scattering, with a rate of k_BT/\u210f, captures the linear temperature dependence of the (dc) electrical resistivity, which is a hallmark of strange metal behavior. Here we extend a previously introduced analysis scheme based of the Drude description of the dc resistivity to optical conductivity data. When they are well described by a simple (ac) Drude model, the scattering rate can be directly extracted. This avoids the need to determine the ratio of charge carrier concentration to effective mass, which has complicated previous analyses based on the dc resistivity. However, we point out that strange metals may exhibit strong deviations from Drude behavior, as exemplified by the \"extreme\" strange metal YbRh\u2082Si\u2082. This calls for alternative approaches, and we point to the power of scaling relationships in terms of temperature and energy (or frequency).", "date": "2022-05-26", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220707-204118082", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220707-204118082", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Postdoctoral Fellowship" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Robert A. Welch Foundation", "grant_number": "C-1509" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-21-1-0356" }, { "agency": "Robert A. Welch Foundation", "grant_number": "C-1411" }, { "agency": "European Research Council (ERC)", "grant_number": "824109" }, { "agency": "FWF Der Wissenschaftsfonds", "grant_number": "29296-N27" }, { "agency": "FWF Der Wissenschaftsfonds", "grant_number": "I5868-N\u2013FOR 5249" }, { "agency": "NSF", "grant_number": "PHY-1607611" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.arXiv.2205.13382", "primary_object": { "basename": "2205.13382.pdf", "url": "https://authors.library.caltech.edu/records/rsb00-t1284/files/2205.13382.pdf" }, "pub_year": "2022", "author_list": "Li, Xinwei; Kono, Junichiro; et el." }, { "id": "https://authors.library.caltech.edu/records/qqvh4-vrf77", "eprint_id": 114895, "eprint_status": "archive", "datestamp": "2023-08-20 07:40:53", "lastmod": "2023-10-24 15:14:56", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Yiran", "name": { "family": "Zhang", "given": "Yiran" }, "orcid": "0000-0002-8477-0074" }, { "id": "Polski-Robert-M", "name": { "family": "Polski", "given": "Robert" }, "orcid": "0000-0003-0887-8099" }, { "id": "Thomson-Alex", "name": { "family": "Thomson", "given": "Alex" }, "orcid": "0000-0002-9938-5048" }, { "id": "Lantagne-Hurtubise-\u00c9tienne", "name": { "family": "Lantagne-Hurtubise", "given": "\u00c9tienne" }, "orcid": "0000-0003-0417-6452" }, { "id": "Lewandowski-Cyprian", "name": { "family": "Lewandowski", "given": "Cyprian" }, "orcid": "0000-0002-6944-9805" }, { "id": "Zhou-Haoxin", "name": { "family": "Zhou", "given": "Haoxin" }, "orcid": "0000-0003-1235-0035" }, { "id": "Watanabe-Kenji", "name": { "family": "Watanabe", "given": "Kenji" }, "orcid": "0000-0003-3701-8119" }, { "id": "Taniguchi-Takashi", "name": { "family": "Taniguchi", "given": "Takashi" }, "orcid": "0000-0002-1467-3105" }, { "id": "Alicea-J", "name": { "family": "Alicea", "given": "Jason" }, "orcid": "0000-0001-9979-3423" }, { "id": "Nadj-Perge-S", "name": { "family": "Nadj-Perge", "given": "Stevan" }, "orcid": "0000-0002-2394-9070" } ] }, "title": "Spin-Orbit Enhanced Superconductivity in Bernal Bilayer Graphene", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nWe thank Andrea Young and Allan Macdonald for fruitful discussions. \n\nThis work has been primarily supported by NSF-CAREER award (DMR-1753306), and Office of Naval Research (grant no. N142112635), and Army Research Office under Grant Award W911NF17-1-0323. Nanofabrication efforts have been in part supported by Department of Energy DOE-QIS program (DE-SC0019166). S.N-P. acknowledges support from the Sloan Foundation (grant no. FG-2020-13716). J.A. and S.N.-P. also acknowledge support of the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation through Grant GBMF1250. C.L. and E.L.H. acknowledge support from the Gordon and Betty Moore Foundation's EPiQS Initiative, grant GBMF8682. \n\nAuthor Contribution: Y.Z. and S.N.-P. designed the experiment. Y.Z., R.P. and H.Z. performed the measurements, fabricated the devices, and analyzed the data. A.T., E.L.-H. and C.L. developed theoretical models and performed calculations supervised by J.A. K.W. and T.T. provided hBN crystals. S.N.-P. supervised the project. Y.Z., A.T., E.L.-H., C.L., H.Z., R.P., J.A., and S.N.-P. wrote the manuscript with the input of other authors. \n\nData availability: The data supporting the findings of this study are available from the corresponding authors on reasonable request. \n\nCode availability: All code used in modeling in this study is available from the corresponding authors on reasonable request. \n\nThe authors declare no competing interests.\n\nSubmitted - 2205.05087.pdf
", "abstract": "In the presence of a large perpendicular electric field, Bernal-stacked bilayer graphene (BLG) features several broken-symmetry metallic phases as well as magnetic-field-induced superconductivity. The superconducting state is quite fragile, however, appearing only in a narrow window of density and with a maximum critical temperature T\ua700 \u2248 30~mK. Here, we show that placing monolayer tungsten diselenide (WSe\u2082) on BLG promotes Cooper pairing to an extraordinary degree: superconductivity appears at zero magnetic field, exhibits an order of magnitude enhancement in T\ua700, and occurs over a density range that is wider by a factor of eight. By mapping quantum oscillations in BLG-WSe\u2082 as a function of electric field and doping, we establish that superconductivity emerges throughout a region whose normal state is polarized, with two out of four spin-valley flavours predominantly populated. In-plane magnetic field measurements further reveal a striking dependence of the critical field on doping, with the Chandrasekhar-Clogston (Pauli) limit roughly obeyed on one end of the superconducting dome yet sharply violated on the other. Moreover, the superconductivity arises only for perpendicular electric fields that push BLG hole wavefunctions towards WSe\u2082 -- suggesting that proximity-induced (Ising) spin-orbit coupling plays a key role in enhancing the pairing. Our results pave the way for engineering robust, highly tunable, and ultra-clean graphene-based superconductors.", "date": "2022-05-24", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220524-180301852", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220524-180301852", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1753306" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N142112635" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF17-1-0323" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019166" }, { "agency": "Alfred P. Sloan Foundation", "grant_number": "FG-2020-13716" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1250" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF8682" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2205.05087", "primary_object": { "basename": "2205.05087.pdf", "url": "https://authors.library.caltech.edu/records/qqvh4-vrf77/files/2205.05087.pdf" }, "pub_year": "2022", "author_list": "Zhang, Yiran; Polski, Robert; et el." }, { "id": "https://authors.library.caltech.edu/records/06ybb-rx004", "eprint_id": 114894, "eprint_status": "archive", "datestamp": "2023-08-20 07:41:02", "lastmod": "2023-10-24 15:14:54", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Polski-Robert-M", "name": { "family": "Polski", "given": "Robert" }, "orcid": "0000-0003-0887-8099" }, { "id": "Zhang-Yiran", "name": { "family": "Zhang", "given": "Yiran" }, "orcid": "0000-0002-8477-0074" }, { "id": "Peng-Yang", "name": { "family": "Peng", "given": "Yang" }, "orcid": "0000-0002-8868-2928" }, { "id": "Arora-Harpreet-Singh", "name": { "family": "Arora", "given": "Harpreet Singh" }, "orcid": "0000-0002-7674-735X" }, { "id": "Choi-Youngjoon", "name": { "family": "Choi", "given": "Youngjoon" }, "orcid": "0000-0001-9783-5992" }, { "id": "Kim-Hyunjin", "name": { "family": "Kim", "given": "Hyunjin" }, "orcid": "0000-0001-9886-0487" }, { "id": "Watanabe-Kenji", "name": { "family": "Watanabe", "given": "Kenji" }, "orcid": "0000-0003-3701-8119" }, { "id": "Taniguchi-Takashi", "name": { "family": "Taniguchi", "given": "Takashi" }, "orcid": "0000-0002-1467-3105" }, { "id": "Refael-G", "name": { "family": "Refael", "given": "Gil" } }, { "id": "von-Oppen-Felix", "name": { "family": "von Oppen", "given": "Felix" }, "orcid": "0000-0002-2537-7256" }, { "id": "Nadj-Perge-S", "name": { "family": "Nadj-Perge", "given": "Stevan" }, "orcid": "0000-0002-2394-9070" } ] }, "title": "Hierarchy of Symmetry Breaking Correlated Phases in Twisted Bilayer Graphene", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nWe acknowledge discussions with Cyprian Lewandowski, Jason Alicea, and Alex Thomson. \n\nThis work has been primarily supported by the DOE-QIS program (DE-SC0019166) and NSF-CAREER (DMR-1753306). S.N-P. acknowledges support from the Sloan Foundation. G.R. and S.N.-P. also acknowledge the support of the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation through Grant GBMF1250; Y.P. acknowledges support from the startup fund from California State University, Northridge. F.v.O. is supported by Deutsche Forschungsgemeinschaft within CRC 183 (project C02) as well as the project TWISTGRAPH. \n\nAuthor Contribution: R.P. and Y.Z. performed the measurements, fabricated devices, and analyzed the data. H.P., Y.C., and H.K. helped with device fabrication and data analysis. Y. P. developed a theoretical model and performed model calculations in close collaboration with F.v.O. and G.R. K.W., and T.T. provides hBN crystals. S.N-P. supervised the project. R.P, Y.Z. Y.P., F.v.O. G.R. and S.N-P. wrote the manuscript with the input of other authors. \n\nData availability: The data that support the findings of this study are available from the corresponding authors on reasonable request. \n\nCode availability: The code that support the findings of this study are available from the corresponding authors on reasonable request. \n\nThe authors declare no competing interests.\n\nSubmitted - 2205.05225.pdf
", "abstract": "Twisted bilayer graphene (TBG) near the magic twist angle of \u223c1.1\u00b0 exhibits a rich phase diagram. However, the interplay between different phases and their dependence on twist angle is still elusive. Here, we explore the stability of various TBG phases and demonstrate that superconductivity near filling of two electrons per moir\u00e9 unit cell alongside Fermi surface reconstructions, as well as entropy-driven high-temperature phase transitions and linear-in-T resistance occur over a range of twist angles which extends far beyond those exhibiting correlated insulating phases. In the vicinity of the magic angle, we also find a metallic phase that displays a hysteretic anomalous Hall effect and incipient Chern insulating behaviour. Such a metallic phase can be rationalized in terms of the interplay between interaction-driven deformations of TBG bands leading to Berry curvature redistribution and Fermi surface reconstruction. Our results provide an extensive perspective on the hierarchy of correlated phases in TBG as classified by their robustness against deviations from the magic angle or, equivalently, their electronic interaction requirements.", "date": "2022-05-24", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220524-180258498", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220524-180258498", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019166" }, { "agency": "NSF", "grant_number": "DMR-1753306" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1250" }, { "agency": "California State University, Northridge" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "CRC 183" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2205.05225", "primary_object": { "basename": "2205.05225.pdf", "url": "https://authors.library.caltech.edu/records/06ybb-rx004/files/2205.05225.pdf" }, "pub_year": "2022", "author_list": "Polski, Robert; Zhang, Yiran; et el." }, { "id": "https://authors.library.caltech.edu/records/2jegc-73t42", "eprint_id": 114511, "eprint_status": "archive", "datestamp": "2023-08-20 07:22:54", "lastmod": "2023-10-24 15:00:28", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Slagle-Kevin", "name": { "family": "Slagle", "given": "Kevin" }, "orcid": "0000-0002-8036-3447" }, { "id": "Liu-Yue", "name": { "family": "Liu", "given": "Yue" }, "orcid": "0000-0002-5965-0644" }, { "id": "Aasen-David", "name": { "family": "Aasen", "given": "David" }, "orcid": "0000-0002-6552-488X" }, { "id": "Pichler-Hannes", "name": { "family": "Pichler", "given": "Hannes" }, "orcid": "0000-0003-2144-536X" }, { "id": "Mong-Roger-S-K", "name": { "family": "Mong", "given": "Roger S. K." } }, { "id": "Chen-Xie", "name": { "family": "Chen", "given": "Xie" } }, { "id": "Endres-M", "name": { "family": "Endres", "given": "Manuel" }, "orcid": "0000-0002-4461-224X" }, { "id": "Alicea-J", "name": { "family": "Alicea", "given": "Jason" }, "orcid": "0000-0001-9979-3423" } ] }, "title": "Quantum spin liquids bootstrapped from Ising criticality in Rydberg arrays", "ispublished": "unpub", "full_text_status": "public", "note": "It is a pleasure to thank Lesik Motrunich, David Mross, and Frederik Nathan for stimulating conversations. We are particularly grateful to Paul Fendley for many illuminating discussions and a prior collaboration that set the foundations of our study. The U.S. Department of Energy, Office of Science, National Quantum Information Science Research Centers, Quantum Science Center supported the construction and analysis of 2D Rydberg array models. The Army Research Office under Grant Award W911NF-17-1-0323 supported the analysis of non-Abelian defects. Additional support was provided by the National Science Foundation through grant DMR-1848336 (RM); the Caltech Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation through Grant GBMF1250; the Walter Burke Institute for Theoretical Physics at Caltech; the ESQ by a Discovery Grant; the Gordon and Betty Moore Foundation's EPiQS Initiative, Grant GBMF8682; and the AFOSR YIP (FA9550-19-1-0044). ME acknowledges support from the NSF QLCI program through grant number OMA-2016245, the DARPA ONISQ program (grant no. W911NF2010021), and the DOE Quantum Systems Accelerator Center (contract no. 7568717).\n\nSubmitted - 2204.00013.pdf
", "abstract": "Arrays of Rydberg atoms constitute a highly tunable, strongly interacting venue for the pursuit of exotic states of matter. We develop a new strategy for accessing a family of fractionalized phases known as quantum spin liquids in two-dimensional Rydberg arrays. We specifically use effective field theory methods to study arrays assembled from Rydberg chains tuned to an Ising phase transition that famously hosts emergent fermions propagating within each chain. This highly entangled starting point allows us to naturally access spin liquids familiar from Kitaev's honeycomb model, albeit from an entirely different framework. In particular, we argue that finite-range repulsive Rydberg interactions, which frustrate nearby symmetry-breaking orders, can enable coherent propagation of emergent fermions between the chains in which they were born. Delocalization of emergent fermions across the full two-dimensional Rydberg array yields a gapless Z2 spin liquid with a single massless Dirac cone. Here, the Rydberg occupation numbers exhibit universal power-law correlations that provide a straightforward experimental diagnostic of this phase. We further show that explicitly breaking symmetries perturbs the gapless spin liquid into gapped, topologically ordered descendants: Breaking lattice symmetries generates toric-code topological order, whereas introducing chirality generates non-Abelian Ising topological order. In the toric-code phase, we analytically construct microscopic incarnations of non-Abelian defects, which can be created and transported by dynamically controlling the atom positions in the array. Our work suggests that appropriately tuned Rydberg arrays provide a cold-atoms counterpart of solid-state 'Kitaev materials' and, more generally, spotlights a new angle for pursuing experimental platforms for Abelian and non-Abelian fractionalization.", "date": "2022-03-31", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220428-212235605", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220428-212235605", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-17-1-0323" }, { "agency": "NSF", "grant_number": "DMR-1848336" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1250" }, { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" }, { "agency": "Erwin Schr\u00f6dinger Center for Quantum Science & Technology (ESQ)" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF8682" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-19-1-0044" }, { "agency": "NSF", "grant_number": "OMA-2016245" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "W911NF-20-10021" }, { "agency": "Quantum Systems Accelerator", "grant_number": "7568717" } ] }, "local_group": { "items": [ { "id": "Walter-Burke-Institute-for-Theoretical-Physics" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2204.00013", "primary_object": { "basename": "2204.00013.pdf", "url": "https://authors.library.caltech.edu/records/2jegc-73t42/files/2204.00013.pdf" }, "pub_year": "2022", "author_list": "Slagle, Kevin; Liu, Yue; et el." }, { "id": "https://authors.library.caltech.edu/records/0pn1a-12057", "eprint_id": 113596, "eprint_status": "archive", "datestamp": "2023-09-15 07:33:31", "lastmod": "2023-10-23 21:36:11", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nathan-Frederik", "name": { "family": "Nathan", "given": "Frederik" }, "orcid": "0000-0001-9700-0231" }, { "id": "Martin-Ivar", "name": { "family": "Martin", "given": "Ivar" }, "orcid": "0000-0002-2010-6449" }, { "id": "Refael-G", "name": { "family": "Refael", "given": "Gil" } } ] }, "title": "Topological frequency conversion in Weyl semimetals", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Mark Rudner, Prineha Narang, Chris Ciccarino, and N. Peter Armitage for valuable discussions. FN gratefully acknowledges the support of the European Research Council (ERC) under the European Union Horizon 2020 Research and Innovation Programme (Grant Agreement No. 678862) and the Villum Foundation. IM was supported by the Materials Sciences and Engineering Division, Basic Energy Sciences, Office of Science, U.S. Department of Energy. GR is grateful for support from the Simons Foundation as well as support from the NSF DMR grant number 1839271. This work is supported by ARO MURI Grant No. W911NF-16-1-0361, and was performed in part at Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611.\n\nSubmitted - 2201.07804.pdf
", "abstract": "We show that a Weyl semimetal irradiated at two distinct frequencies can convert energy between the frequencies at a potentially large rate. The phenomenon is a realization of topological frequency conversion from [Martin et al, PRX 7 041008 (2017)]. When the effect is realized, each electron near a Weyl point acts as a topological frequency converter, and converts energy at a universal rate given by Planck's constant multiplied by the product of the two frequencies. Our results indicate that Weyl points in TaAs support topological frequency conversion in the THz regime at achievable intensities of order 100 W/mm2. When the topological energy conversion rate exceeds the dissipation rate, the effect can be used for optical amplification. This amplification regime can be achieved when the relaxation rate of the system is larger than the characteristic driving period. This phenomenon further amplifies Weyl semimetals' promise for optical amplification and terahertz (THz) generation.", "date": "2022-02-28", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220224-200907852", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220224-200907852", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Research Council (ERC)", "grant_number": "678862" }, { "agency": "Villum Foundation" }, { "agency": "Department of Energy (DOE)" }, { "agency": "Simons Foundation" }, { "agency": "NSF", "grant_number": "DMR-1839271" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-16-1-0361" }, { "agency": "NSF", "grant_number": "PHY-1607611" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2201.07804", "primary_object": { "basename": "2201.07804.pdf", "url": "https://authors.library.caltech.edu/records/0pn1a-12057/files/2201.07804.pdf" }, "pub_year": "2022", "author_list": "Nathan, Frederik; Martin, Ivar; et el." }, { "id": "https://authors.library.caltech.edu/records/3wwg1-yjh32", "eprint_id": 113225, "eprint_status": "archive", "datestamp": "2023-08-20 06:16:25", "lastmod": "2023-10-23 22:59:28", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Chi-Fang", "name": { "family": "Chen", "given": "Chi-Fang" }, "orcid": "0000-0001-5589-7896" }, { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" } ] }, "title": "Fast Thermalization from the Eigenstate Thermalization Hypothesis", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Charles Xu for early discussions on the topic of this paper. We thank Robert (Hsin-Yuan) Huang for suggesting to check quantum expander properties numerically. We thank Cambyse Rouz\u2002 for discussions on approximate tensorization. CFC is supported by Caltech RA fellowship and the Eddleman Fellowship.\n\nSubmitted - 2112.07646.pdf
", "abstract": "The Eigenstate Thermalization Hypothesis (ETH) has played a major role in explaining thermodynamic phenomena in quantum systems. However, so far, no connection has been known between ETH and the timescale of thermalization. In this paper, we rigorously show that ETH indeed implies fast thermalization to the global Gibbs state. We show fast convergence for two models of thermalization. In the first, the system is weakly coupled to a bath of (quasi)-free Fermions that we control. We derive a finitely-resolved version of Davies' generator, with explicit error bounds and resource estimates, that describes the joint evolution at finite times. The second is Quantum Metropolis Sampling, a quantum algorithm for preparing Gibbs states on a quantum computer. In both cases, no guarantee for fast convergence was previously known for non-commuting Hamiltonians, partly due to technical issues with a finite energy resolution. The critical feature of ETH we exploit is that the Hamiltonian can be modeled by random matrix theory below a sufficiently small energy scale. We show this gives quantum expander at nearby eigenstates of the Hamiltonian. This then implies fast convergence to the global Gibbs state by mapping the problem to a one-dimensional classical random walk on the spectrum of the Hamiltonian. Our results explain finite-time thermalization in chaotic open quantum systems and suggest an alternative formulation of ETH in terms of quantum expanders, which we confirm numerically for small systems.", "date": "2022-02-02", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220202-191908990", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220202-191908990", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech" }, { "agency": "Eddleman Fellowship" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "AWS-Center-for-Quantum-Computing" } ] }, "doi": "10.48550/arXiv.2112.07646", "primary_object": { "basename": "2112.07646.pdf", "url": "https://authors.library.caltech.edu/records/3wwg1-yjh32/files/2112.07646.pdf" }, "pub_year": "2022", "author_list": "Chen, Chi-Fang and Brand\u00e3o, Fernando G. S. L." }, { "id": "https://authors.library.caltech.edu/records/24n4d-brx37", "eprint_id": 113224, "eprint_status": "archive", "datestamp": "2023-08-20 06:13:35", "lastmod": "2023-10-23 22:59:25", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhu-Daiwei", "name": { "family": "Zhu", "given": "Daiwei" } }, { "id": "Kahanamoku-Meyer-Gregory-D", "name": { "family": "Kahanamoku-Meyer", "given": "Gregory D." } }, { "id": "Lewis-Laura", "name": { "family": "Lewis", "given": "Laura" } }, { "id": "Noel-Crystal", "name": { "family": "Noel", "given": "Crystal" } }, { "id": "Katz-Or", "name": { "family": "Katz", "given": "Or" } }, { "id": "Harraz-Bahaa", "name": { "family": "Harraz", "given": "Bahaa" } }, { "id": "Wang-Qingfeng", "name": { "family": "Wang", "given": "Qingfeng" } }, { "id": "Risinger-Andrew", "name": { "family": "Risinger", "given": "Andrew" } }, { "id": "Feng-Lei", "name": { "family": "Feng", "given": "Lei" } }, { "id": "Biswas-Debopriyo", "name": { "family": "Biswas", "given": "Debopriyo" } }, { "id": "Egan-Laird", "name": { "family": "Egan", "given": "Laird" } }, { "id": "Gheorghiu-Alexandru", "name": { "family": "Gheorghiu", "given": "Alexandru" }, "orcid": "0000-0001-6225-7168" }, { "id": "Nam-Yunseong", "name": { "family": "Nam", "given": "Yunseong" } }, { "id": "Vidick-T", "name": { "family": "Vidick", "given": "Thomas" }, "orcid": "0000-0002-6405-365X" }, { "id": "Vazirani-Umesh-V", "name": { "family": "Vazirani", "given": "Umesh" } }, { "id": "Yao-Norman-Y", "name": { "family": "Yao", "given": "Norman Y." }, "orcid": "0000-0003-0194-7266" }, { "id": "Cetina-Marko", "name": { "family": "Cetina", "given": "Marko" } }, { "id": "Monroe-Christopher", "name": { "family": "Monroe", "given": "Christopher" } } ] }, "title": "Interactive Protocols for Classically-Verifiable Quantum Advantage", "ispublished": "unpub", "full_text_status": "public", "note": "The authors are grateful to Vivian Uhlir for the design of the verifier and prover figures. This work is supported by the ARO through the IARPA LogiQ program, the U.S. Department of Energy, Office of Science, National Quantum Information Science Research Centers, Quantum Systems Accelerator (QSA), the AFOSR MURIs on Quantum Measurement/Verification and Quantum Interactive Protocols (FA9550-18-1-0161) and Dissipation Engineering in Open Quantum Systems, the NSF STAQ Program, the ARO MURI on Modular Quantum Circuits, the DoE ASCR Accelerated Research in Quantum Computing program (award No. DE-SC0020312), the AFOSR YIP award number FA9550-16-1-0495, the NSF QLCI program through grant number OMA-2016245, the IQIM, an NSF Physics Frontiers Center (NSF Grant PHY-1125565), the Gordon and Betty Moore Foundation (GBMF-12500028), the Dr. Max R\u00f6ssler, the Walter Haefner Foundation and the ETH Z\u00fcrich Foundation, the NSF award DMR-1747426, a Vannever Bush Faculty Fellowship, the Office of Advanced Scientific Computing Research, under the Accelerated Research in Quantum Computing (ARQC) program, the A. P. Sloan foundation and the David and Lucile Packard Foundation. \n\nCompeting interests: C.M. is Chief Scientist for IonQ, Inc. and has a personal financial interest in the company.\n\nSubmitted - 2112.05156.pdf
", "abstract": "Achieving quantum computational advantage requires solving a classically intractable problem on a quantum device. Natural proposals rely upon the intrinsic hardness of classically simulating quantum mechanics; however, verifying the output is itself classically intractable. On the other hand, certain quantum algorithms (e.g. prime factorization via Shor's algorithm) are efficiently verifiable, but require more resources than what is available on near-term devices. One way to bridge the gap between verifiability and implementation is to use \"interactions\" between a prover and a verifier. By leveraging cryptographic functions, such protocols enable the classical verifier to enforce consistency in a quantum prover's responses across multiple rounds of interaction. In this work, we demonstrate the first implementation of an interactive quantum advantage protocol, using an ion trap quantum computer. We execute two complementary protocols -- one based upon the learning with errors problem and another where the cryptographic construction implements a computational Bell test. To perform multiple rounds of interaction, we implement mid-circuit measurements on a subset of trapped ion qubits, with subsequent coherent evolution. For both protocols, the performance exceeds the asymptotic bound for classical behavior; maintaining this fidelity at scale would conclusively demonstrate verifiable quantum advantage.", "date": "2022-02-02", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220202-191905591", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220202-191905591", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Research Office (ARO)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0020312" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0161" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0495" }, { "agency": "NSF", "grant_number": "OMA-2016245" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" }, { "agency": "Dr. Max R\u00f6ssler" }, { "agency": "Walter Haefner Foundation" }, { "agency": "ETH Z\u00fcrich Foundation" }, { "agency": "NSF", "grant_number": "DMR-1747426" }, { "agency": "Vannever Bush Faculty Fellowship" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "David and Lucile Packard Foundation" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2112.05156", "primary_object": { "basename": "2112.05156.pdf", "url": "https://authors.library.caltech.edu/records/24n4d-brx37/files/2112.05156.pdf" }, "pub_year": "2022", "author_list": "Zhu, Daiwei; Kahanamoku-Meyer, Gregory D.; et el." }, { "id": "https://authors.library.caltech.edu/records/13x1a-by718", "eprint_id": 112898, "eprint_status": "archive", "datestamp": "2023-08-20 06:11:52", "lastmod": "2023-10-23 22:50:22", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Xie", "name": { "family": "Chen", "given": "Xie" } }, { "id": "Dua-Arpit", "name": { "family": "Dua", "given": "Arpit" } }, { "id": "Hsin-Po-Shen", "name": { "family": "Hsin", "given": "Po-Shen" }, "orcid": "0000-0002-4764-1476" }, { "id": "Jian-Chao-Ming", "name": { "family": "Jian", "given": "Chao-Ming" } }, { "id": "Shirley-Wilbur-E", "name": { "family": "Shirley", "given": "Wilbur" } }, { "id": "Xu-Cenke", "name": { "family": "Xu", "given": "Cenke" } } ] }, "title": "Loops in 4+1d Topological Phases", "ispublished": "unpub", "full_text_status": "public", "note": "We would like to thank Fiona Burnell, Meng Cheng, Lukasz Fidkowski, Jeongwan Haah, Yi Ni, Xiao-Liang Qi, Nathan Seiberg, Shu-Heng Shao, Kevin Walker and Zhenghan Wang for valuable discussions. A.D. thanks Yu-An Chen for the useful discussion on higher cup products. W.S., A.D., and X.C. were supported by the Simons Foundation through the collaboration on Ultra-Quantum Matter (651438, XC), the Walter Burke Institute of Theoretical Physics, the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (PHY-1733907), the National Science Foundation (DMR-1654340, XC) and the Simons Investigator Award (828078, XC). W.S. is also supported by a grant from the Simons Foundation (651444, WS). The work of P.-S. H. is supported by the U.S. Department of Energy, Office of Science, Office of High Energy Physics, under Award Number DE-SC0011632, by the Simons Foundation through the Simons Investigator Award, and by the Simons Collaboration on Global Categorical Symmetries. C. X. is supported by NSF Grant No. DMR-1920434 and the Simons Investigator program.\n\nSubmitted - 2112.02137.pdf
", "abstract": "2+1d topological phases are well characterized by the fusion rules and braiding/exchange statistics of fractional point excitations. In 4+1d, some topological phases contain only fractional loop excitations. What kind of loop statistics exist? We study the 4+1d gauge theory with 2-form \u2124\u2082 gauge field (the loop only toric code) and find that while braiding statistics between two different types of loops can be nontrivial, the self `exchange' statistics are all trivial. In particular, we show that the electric, magnetic, and dyonic loop excitations in the 4+1d toric code are not distinguished by their self-statistics. They tunnel into each other across 3+1d invertible domain walls which in turn give explicit unitary circuits that map the loop excitations into each other. The SL(2,\u2124\u2082) symmetry that permutes the loops, however, cannot be consistently gauged and we discuss the associated obstruction in the process. Moreover, we discuss a gapless boundary condition dubbed the 'fractional Maxwell theory' and show how it can be Higgsed into gapped boundary conditions. We also discuss the generalization of these results from the \u2124\u2082 gauge group to \u2124_N.", "date": "2022-01-14", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220113-234540268", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220113-234540268", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Simons Foundation", "grant_number": "651438" }, { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1733907" }, { "agency": "NSF", "grant_number": "DMR-1654340" }, { "agency": "Simons Foundation", "grant_number": "828078" }, { "agency": "Simons Foundation", "grant_number": "651444" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0011632" }, { "agency": "NSF", "grant_number": "DMR-1920434" } ] }, "local_group": { "items": [ { "id": "Walter-Burke-Institute-for-Theoretical-Physics" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2112.02137", "primary_object": { "basename": "2112.02137.pdf", "url": "https://authors.library.caltech.edu/records/13x1a-by718/files/2112.02137.pdf" }, "pub_year": "2022", "author_list": "Chen, Xie; Dua, Arpit; et el." }, { "id": "https://authors.library.caltech.edu/records/n990w-e2f28", "eprint_id": 112906, "eprint_status": "archive", "datestamp": "2023-08-20 06:20:08", "lastmod": "2023-10-23 22:50:44", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Yiran", "name": { "family": "Zhang", "given": "Yiran" }, "orcid": "0000-0002-8477-0074" }, { "id": "Polski-Robert-M", "name": { "family": "Polski", "given": "Robert" }, "orcid": "0000-0003-0887-8099" }, { "id": "Lewandowski-Cyprian", "name": { "family": "Lewandowski", "given": "Cyprian" }, "orcid": "0000-0002-6944-9805" }, { "id": "Thomson-Alex", "name": { "family": "Thomson", "given": "Alex" }, "orcid": "0000-0002-9938-5048" }, { "id": "Peng-Yang", "name": { "family": "Peng", "given": "Yang" }, "orcid": "0000-0002-8868-2928" }, { "id": "Choi-Youngjoon", "name": { "family": "Choi", "given": "Youngjoon" } }, { "id": "Kim-Hyunjin", "name": { "family": "Kim", "given": "Hyunjin" }, "orcid": "0000-0001-9886-0487" }, { "id": "Watanabe-Kenji", "name": { "family": "Watanabe", "given": "Kenji" }, "orcid": "0000-0003-3701-8119" }, { "id": "Taniguchi-Takashi", "name": { "family": "Taniguchi", "given": "Takashi" }, "orcid": "0000-0002-1467-3105" }, { "id": "Alicea-J", "name": { "family": "Alicea", "given": "Jason" }, "orcid": "0000-0001-9979-3423" }, { "id": "von-Oppen-Felix", "name": { "family": "von Oppen", "given": "Felix" }, "orcid": "0000-0002-2537-7256" }, { "id": "Refael-G", "name": { "family": "Refael", "given": "Gil" } }, { "id": "Nadj-Perge-S", "name": { "family": "Nadj-Perge", "given": "Stevan" }, "orcid": "0000-0002-2394-9070" } ] }, "title": "Ascendance of Superconductivity in Magic-Angle Graphene Multilayers", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nWe thank Haoxin Zhou and Soudabeh Mashahadi for fruitful discussions. \n\nThis work has been primarily supported by NSF-CAREER award (DMR-1753306), and Office of Naval Research (grant no. N142112635), and Army Research Office under Grant Award W911NF17-1-0323. Nanofabrication efforts have been in part supported by Department of Energy DOE-QIS program (DE-SC0019166). S.N-P. acknowledges support from the Sloan Foundation (grant no. FG-2020-13716). G.R., J.A., and S.N.-P. also acknowledge support of the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation through Grant GBMF1250. C.L. acknowledges support from the Gordon and Betty Moore Foundation's EPiQS Initiative, grant GBMF8682. Y.P. acknowledges support from the startup fund from California State University, Northridge. F.v.O. is supported by CRC 183 (project C02) of Deutsche Forschungsgemeinschaft. \n\nAuthor Contribution: Y.Z. and R.P. performed the measurements, fabricated the devices, and analyzed the data. Y.C. and H.K. helped with device fabrication and data analysis. C.L., A.T. and Y.P. developed theoretical models and performed calculations in close collaboration and guidance by F.v.O., G.R. and J.A. K.W. and T.T. provides hBN crystals. S.N-P. supervised the project. Y.Z., R.P., C.L., A.T., Y.P., F.v.O., G.R., J.A., and S.N-P. wrote the manuscript with the input of other authors. \n\nThe authors declare no competing interests. \n\nData availability: The data supporting the findings of this study are available from the corresponding authors on reasonable request. \n\nCode availability: All code used in modeling in this study is available from the corresponding authors on reasonable request.\n\nSubmitted - 2112.09270.pdf
", "abstract": "Graphene moire superlattices have emerged as a platform hosting and abundance of correlated insulating, topological, and superconducting phases. While the origins of strong correlations and non-trivial topology are shown to be directly linked to flat moire bands, the nature and mechanism of superconductivity remain enigmatic. In particular, only alternating twisted stacking geometries of bilayer and trilayer graphene are found to exhibit robust superconductivity manifesting as zero resistance and Fraunhofer interference patterns. Here we demonstrate that magic-angle twisted tri-, quadri-, and pentalayers placed on monolayer tungsten diselenide exhibit flavour polarization and superconductivity. We also observe insulating states in the trilayer and quadrilayer arising at finite electric displacement fields, despite the presence of dispersive bands introduced by additional graphene layers. Moreover, the three multilayer geometries allow us to identify universal features in the family of graphene moire structures arising from the intricate relations between superconducting states, symmetry-breaking transitions, and van Hove singularities. Remarkably, as the number of layers increases, superconductivity emerges over a dramatically enhanced filling-factor range. In particular, in twisted pentalayers, superconductivity extends well beyond the filling of four electrons per moire unit cell, demonstrating the non-trivial role of the additional bands. Our results highlight the importance of the interplay between flat and dispersive bands in extending superconducting regions in graphene moire superlattices and open new frontiers for developing graphene-based superconductors.", "date": "2022-01-14", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220113-234609742", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220113-234609742", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1753306" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N142112635" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF17-1-0323" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019166" }, { "agency": "Alfred P. Sloan Foundation", "grant_number": "FG-2020-13716" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1250" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF8682" }, { "agency": "California State University, Northridge" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "CRC 183" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2112.09270", "primary_object": { "basename": "2112.09270.pdf", "url": "https://authors.library.caltech.edu/records/n990w-e2f28/files/2112.09270.pdf" }, "pub_year": "2022", "author_list": "Zhang, Yiran; Polski, Robert; et el." }, { "id": "https://authors.library.caltech.edu/records/z351a-qyb72", "eprint_id": 112871, "eprint_status": "archive", "datestamp": "2023-08-20 05:35:50", "lastmod": "2023-10-23 22:49:28", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tong-Yu", "name": { "family": "Tong", "given": "Yu" } }, { "id": "Albert-Victor-V", "name": { "family": "Albert", "given": "Victor V." }, "orcid": "0000-0002-0335-9508" }, { "id": "McClean-Jarrod-R", "name": { "family": "McClean", "given": "Jarrod R." }, "orcid": "0000-0002-2809-0509" }, { "id": "Preskill-J", "name": { "family": "Preskill", "given": "John" }, "orcid": "0000-0002-2421-4762" }, { "id": "Su-Yuan", "name": { "family": "Su", "given": "Yuan" }, "orcid": "0000-0003-1144-3563" } ] }, "title": "Provably accurate simulation of gauge theories and bosonic systems", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Kunal Sharma, Mark Wilde, Minh Cong Tran, Junyu Liu, Chi-Fang (Anthony) Chen, Ryan Babbush, Joonho Lee, Di Luo, Nathan Wiebe, Dominic Berry, and Lin Lin for helpful discussions. YT was partly supported by the NSF Quantum Leap Challenge Institute (QLCI) program through Grant No. OMA-2016245, and by the Department of Energy under Grant No. FWP-NQISCCAWL. JP was partly supported by the U.S. Department of Energy Office of Advanced Scientific Computing Research (DE-NA0003525, DE-SC0020290) and Office of High Energy Physics (DE-ACO2-07CH11359, DE-SC0018407), the Simons Foundation It from Qubit Collaboration, the Air Force Office of Scientific Research (FA9550-19-1-0360), and the National Science Foundation (PHY-1733907). YS was partly supported by the National Science Foundation RAISE-TAQS 1839204. The Institute for Quantum Information and Matter is an NSF Physics Frontiers Center. Contributions to this work by NIST, an agency of the US government, are not subject to US copyright. Any mention of commercial products does not indicate endorsement by NIST.\n\nSubmitted - 2110.06942.pdf
", "abstract": "Quantum many-body systems involving bosonic modes or gauge fields have infinite-dimensional local Hilbert spaces which must be truncated to perform simulations of real-time dynamics on classical or quantum computers. To analyze the truncation error, we develop methods for bounding the rate of growth of local quantum numbers such as the occupation number of a mode at a lattice site, or the electric field at a lattice link. Our approach applies to various models of bosons interacting with spins or fermions, and also to both abelian and non-abelian gauge theories. We show that if states in these models are truncated by imposing an upper limit \u039b on each local quantum number, and if the initial state has low local quantum numbers, then an error at most \u03f5 can be achieved by choosing \u039b to scale polylogarithmically with \u03f5\u207b\u00b9, an exponential improvement over previous bounds based on energy conservation. For the Hubbard-Holstein model, we numerically compute a bound on \u039b that achieves accuracy \u03f5, obtaining significantly improved estimates in various parameter regimes. We also establish a criterion for truncating the Hamiltonian with a provable guarantee on the accuracy of time evolution. Building on that result, we formulate quantum algorithms for dynamical simulation of lattice gauge theories and of models with bosonic modes; the gate complexity depends almost linearly on spacetime volume in the former case, and almost quadratically on time in the latter case. We establish a lower bound showing that there are systems involving bosons for which this quadratic scaling with time cannot be improved. By applying our result on the truncation error in time evolution, we also prove that spectrally isolated energy eigenstates can be approximated with accuracy \u03f5 by truncating local quantum numbers at \u039b = polylog(\u03f5\u207b\u00b9).", "date": "2022-01-13", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220113-182219174", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220113-182219174", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "OMA-2016245" }, { "agency": "Department of Energy (DOE)", "grant_number": "FWP-NQISCCAWL" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-NA0003525" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0020290" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-ACO2-07CH11359" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0018407" }, { "agency": "Simons Foundation" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-19-1-0360" }, { "agency": "NSF", "grant_number": "PHY-1733907" }, { "agency": "NSF", "grant_number": "CCF-1839204" } ] }, "local_group": { "items": [ { "id": "AWS-Center-for-Quantum-Computing" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2110.06942", "primary_object": { "basename": "2110.06942.pdf", "url": "https://authors.library.caltech.edu/records/z351a-qyb72/files/2110.06942.pdf" }, "pub_year": "2022", "author_list": "Tong, Yu; Albert, Victor V.; et el." }, { "id": "https://authors.library.caltech.edu/records/sz595-h0961", "eprint_id": 112870, "eprint_status": "archive", "datestamp": "2023-08-20 05:11:45", "lastmod": "2023-10-23 22:49:25", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Hyunjin", "name": { "family": "Kim", "given": "Hyunjin" }, "orcid": "0000-0001-9886-0487" }, { "id": "Choi-Youngjoon", "name": { "family": "Choi", "given": "Youngjoon" } }, { "id": "Lewandowski-Cyprian", "name": { "family": "Lewandowski", "given": "Cyprian" }, "orcid": "0000-0002-6944-9805" }, { "id": "Thomson-Alex", "name": { "family": "Thomson", "given": "Alex" }, "orcid": "0000-0002-9938-5048" }, { "id": "Zhang-Yiran", "name": { "family": "Zhang", "given": "Yiran" }, "orcid": "0000-0002-8477-0074" }, { "id": "Polski-Robert-M", "name": { "family": "Polski", "given": "Robert" }, "orcid": "0000-0003-0887-8099" }, { "id": "Watanabe-Kenji", "name": { "family": "Watanabe", "given": "Kenji" }, "orcid": "0000-0003-3701-8119" }, { "id": "Taniguchi-Takashi", "name": { "family": "Taniguchi", "given": "Takashi" }, "orcid": "0000-0002-1467-3105" }, { "id": "Alicea-J", "name": { "family": "Alicea", "given": "Jason" }, "orcid": "0000-0001-9979-3423" }, { "id": "Nadj-Perge-S", "name": { "family": "Nadj-Perge", "given": "Stevan" }, "orcid": "0000-0002-2394-9070" } ] }, "title": "Spectroscopic Signatures of Strong Correlations and Unconventional Superconductivity in Twisted Trilayer Graphene", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nWe acknowledge discussions with Felix von Oppen, Gil Refael, Yang Peng, and Ali Yazdani. \n\nThis work has been primarily supported by Office of Naval Research (grant no. N142112635); National Science Foundation (grant no. DMR-2005129); and Army Research Office under Grant Award W911NF17-1-0323. Nanofabrication efforts have been in part supported by Department of Energy DOE-QIS program (DE-SC0019166). S.N-P. acknowledges support from the Sloan Foundation. J.A. and S.N.-P. also acknowledge support of the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation through Grant GBMF1250; C.L. acknowledges support from the Gordon and Betty Moore Foundation's EPiQS Initiative, Grant GBMF8682. A.T. and J.A. are grateful for the support of the Walter Burke Institute for Theoretical Physics at Caltech. H.K. and Y.C. acknowledge support from the Kwanjeong fellowship. \n\nAuthor Contribution: H.K. and Y.C. fabricated samples with the help of Y.Z. and R.P., and performed STM measurements. H.K., Y.C., and S.N.-P. analyzed the data. C.L. and A.T. provided the theoretical analysis supervised by J.A. S.N.-P. supervised the project. H.K., Y.C., C.L., A.T., J.A., and S.N.-P. wrote the manuscript with input from other authors. \n\nData availability: The data that support the findings of this study are available from the corresponding authors on reasonable request.\n\nSubmitted - 2109.12127.pdf
", "abstract": "Magic-angle twisted trilayer graphene (MATTG) has emerged as a novel moir\u00e9 material that exhibits both strong electronic correlations and unconventional superconductivity. However, spectroscopic studies of its electronic properties are lacking, and the nature of superconductivity and the corresponding order parameter in this system remain elusive. Here we perform high-resolution scanning tunneling microscopy and spectroscopy of MATTG and reveal extensive regions of atomic reconstruction that favor mirror-symmetric stacking. In these regions, we observe a cascade of symmetry-breaking electronic transitions and doping-dependent band structure deformations similar to those realized in magic-angle bilayers, as expected theoretically given the commonality of flat bands. More strikingly, in a density window spanning two to three holes per moire unit cell, spectroscopic signatures of superconductivity are manifest as pronounced dips in the tunneling conductance at the Fermi level accompanied by coherence peaks that become gradually suppressed at elevated temperatures and magnetic fields. The observed evolution of the conductance with doping is consistent with a gate-tunable transition from a gapped to a nodal superconductor, which we show theoretically is compatible with a sharp transition from a Bardeen-Cooper-Schrieffer (BCS) to a Bose-Einstein condensation (BEC) superconductor with a nodal order parameter. Within this doping window, we also detect peak-dip-hump structures suggesting that superconductivity is driven by strong coupling to bosonic modes of MATTG. Our results pave the way for further understanding of superconductivity and correlated states in graphene-based moir\u00e9 structures beyond twisted bilayers, where unconventional superconductivity and nodal pairing were reported.", "date": "2022-01-13", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220113-182215445", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220113-182215445", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N142112635" }, { "agency": "NSF", "grant_number": "DMR-2005129" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF17-1-0323" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019166" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1250" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF8682" }, { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" }, { "agency": "Kwanjeong Educational Foundation" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.2109.12127", "primary_object": { "basename": "2109.12127.pdf", "url": "https://authors.library.caltech.edu/records/sz595-h0961/files/2109.12127.pdf" }, "pub_year": "2022", "author_list": "Kim, Hyunjin; Choi, Youngjoon; et el." }, { "id": "https://authors.library.caltech.edu/records/2vwsn-wzz50", "eprint_id": 112704, "eprint_status": "archive", "datestamp": "2023-08-20 03:48:58", "lastmod": "2023-10-23 22:42:46", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Hsin-Yuan-Robert", "name": { "family": "Huang", "given": "Hsin-Yuan" }, "orcid": "0000-0001-5317-2613" }, { "id": "Kueng-Richard-J", "name": { "family": "Kueng", "given": "Richard" }, "orcid": "0000-0002-8291-648X" }, { "id": "Torlai-Giacomo", "name": { "family": "Torlai", "given": "Giacomo" }, "orcid": "0000-0001-8478-4436" }, { "id": "Albert-Victor-V", "name": { "family": "Albert", "given": "Victor V." }, "orcid": "0000-0002-0335-9508" }, { "id": "Preskill-J", "name": { "family": "Preskill", "given": "John" }, "orcid": "0000-0002-2421-4762" } ] }, "title": "Provably efficient machine learning for quantum many-body problems", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nThe authors thank Nir Bar-Gill, Juan Carrasquilla, Sitan Chen, Yifan Chen, Matthew Fishman, Scott Glancy, Jeongwan Haah, Felix Kueng, Jarrod McClean, Spiros Michalakis, Jacob Taylor, Yuan Su, and Thomas Vidick for valuable input and inspiring discussions. HH thanks Andreas Elben for providing the code on bond-alternating XXZ model. The numerical simulations were performed on AWS EC2 computing infra-structure, using the software packages ITensors [65] and PastaQ [64]. HH is supported by the J. Yang & Family Foundation. JP acknowledges funding from the U.S. Department of Energy Office of Science, Office of Advanced Scientific Computing Research, (DE-NA0003525, DE-SC0020290), and the National Science Foundation (PHY-1733907). The Institute for Quantum Information and Matter is an NSF Physics Frontiers Center. Contributions to this work by NIST, an agency of the US government, are not subject to US copyright. Any mention of commercial products does not indicate endorsement by NIST. VVA thanks Olga Albert, Halina and Ryhor Kandratsenia, as well as Tatyana and Thomas Albert for providing daycare support throughout this work.\n\nSubmitted - 2106.12627.pdf
", "abstract": "Classical machine learning (ML) provides a potentially powerful approach to solving challenging quantum many-body problems in physics and chemistry. However, the advantages of ML over more traditional methods have not been firmly established. In this work, we prove that classical ML algorithms can efficiently predict ground state properties of gapped Hamiltonians in finite spatial dimensions, after learning from data obtained by measuring other Hamiltonians in the same quantum phase of matter. In contrast, under widely accepted complexity theory assumptions, classical algorithms that do not learn from data cannot achieve the same guarantee. We also prove that classical ML algorithms can efficiently classify a wide range of quantum phases of matter. Our arguments are based on the concept of a classical shadow, a succinct classical description of a many-body quantum state that can be constructed in feasible quantum experiments and be used to predict many properties of the state. Extensive numerical experiments corroborate our theoretical results in a variety of scenarios, including Rydberg atom systems, 2D random Heisenberg models, symmetry-protected topological phases, and topologically ordered phases.", "date": "2022-01-11", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220104-233146603", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220104-233146603", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "J. Yang Family and Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-NA0003525" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0020290" }, { "agency": "NSF", "grant_number": "PHY-1733907" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "AWS-Center-for-Quantum-Computing" } ] }, "doi": "10.48550/arXiv.2106.12627", "primary_object": { "basename": "2106.12627.pdf", "url": "https://authors.library.caltech.edu/records/2vwsn-wzz50/files/2106.12627.pdf" }, "pub_year": "2022", "author_list": "Huang, Hsin-Yuan; Kueng, Richard; et el." }, { "id": "https://authors.library.caltech.edu/records/7a1kp-n1n25", "eprint_id": 112385, "eprint_status": "archive", "datestamp": "2023-08-20 06:03:08", "lastmod": "2023-10-23 22:31:21", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dalzell-Alexander-M", "name": { "family": "Dalzell", "given": "Alexander M." }, "orcid": "0000-0002-3756-8500" }, { "id": "Hunter-Jones-Nicholas", "name": { "family": "Hunter-Jones", "given": "Nicholas" }, "orcid": "0000-0001-8578-1958" }, { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" } ] }, "title": "Random quantum circuits transform local noise into global white noise", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Adam Bouland, Bill Fefferman, Zeph Landau, Yunchao Liu, Oskar Painter, John Preskill, and Thomas Vidick for helpful feedback about this work. AD and FB acknowledge funding provided by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NSF Grant PHY-1733907). This material is also based upon work supported by the NSF Graduate Research Fellowship under Grant No. DGE-1745301. NHJ is supported in part by the Stanford Q-FARM Bloch Fellowship in Quantum Science and Engineering. NHJ would like to thank the Aspen Center for Physics for its hospitality during the completion of part of this work. Research at Perimeter Institute is supported in part by the Government of Canada through the Department of Innovation, Science and Economic Development Canada and by the Province of Ontario through the Ministry of Colleges and Universities.\n\nSubmitted - 2111.14907.pdf
", "abstract": "We study the distribution over measurement outcomes of noisy random quantum circuits in the low-fidelity regime. We show that, for local noise that is sufficiently weak and unital, correlations (measured by the linear cross-entropy benchmark) between the output distribution p_(noisy) of a generic noisy circuit instance and the output distribution pideal of the corresponding noiseless instance shrink exponentially with the expected number of gate-level errors, as F = exp(\u22122s\u03f5 \u00b1 O(s\u03f5\u00b2)), where \u03f5 is the probability of error per circuit location and s is the number of two-qubit gates. Furthermore, if the noise is incoherent, the output distribution approaches the uniform distribution p_(unif) at precisely the same rate and can be approximated as p_(noisy) \u2248 F_(p_(ideal)) + (1\u2212F)p_(unif), that is, local errors are scrambled by the random quantum circuit and contribute only white noise (uniform output). Importantly, we upper bound the total variation error (averaged over random circuit instance) in this approximation as O(F\u03f5\u221as), so the \"white-noise approximation\" is meaningful when \u03f5\u221as \u226a 1, a quadratically weaker condition than the \u03f5s\u226a1 requirement to maintain high fidelity. The bound applies when the circuit size satisfies s \u2265 \u03a9(nlog(n)) and the inverse error rate satisfies \u03f5\u207b\u00b9 \u2265 \u03a9\u0303 (n). The white-noise approximation is useful for salvaging the signal from a noisy quantum computation; it was an underlying assumption in complexity-theoretic arguments that low-fidelity random quantum circuits cannot be efficiently sampled classically. Our method is based on a map from second-moment quantities in random quantum circuits to expectation values of certain stochastic processes for which we compute upper and lower bounds.", "date": "2021-12-14", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20211213-224949608", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211213-224949608", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-1733907" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Stanford University" }, { "agency": "Department of Innovation, Science and Economic Development (Canada)" }, { "agency": "Ontario Ministry of Colleges and Universities" } ] }, "local_group": { "items": [ { "id": "AWS-Center-for-Quantum-Computing" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2111.14907", "primary_object": { "basename": "2111.14907.pdf", "url": "https://authors.library.caltech.edu/records/7a1kp-n1n25/files/2111.14907.pdf" }, "pub_year": "2021", "author_list": "Dalzell, Alexander M.; Hunter-Jones, Nicholas; et el." }, { "id": "https://authors.library.caltech.edu/records/gnrr3-rdt94", "eprint_id": 112878, "eprint_status": "archive", "datestamp": "2023-08-20 06:01:31", "lastmod": "2023-10-23 22:49:47", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Albert-Victor-V", "name": { "family": "Albert", "given": "Victor V." }, "orcid": "0000-0002-0335-9508" }, { "id": "Aasen-David", "name": { "family": "Aasen", "given": "David" }, "orcid": "0000-0002-6552-488X" }, { "id": "Xu-Wenqing-William", "name": { "family": "Xu", "given": "Wenqing" } }, { "id": "Ji-Wenjie", "name": { "family": "Ji", "given": "Wenjie" } }, { "id": "Alicea-J", "name": { "family": "Alicea", "given": "Jason" }, "orcid": "0000-0001-9979-3423" }, { "id": "Preskill-J", "name": { "family": "Preskill", "given": "John" }, "orcid": "0000-0002-2421-4762" } ] }, "title": "Spin chains, defects, and quantum wires for the quantum-double edge", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nWe thank Daniel Arovas, Maissam Barkeshli, Barry Bradlyn, Michele Burrello, Aaron Chew, Iris Cong, Jan von Delft, Paul Fendley, Hrant Gharibyan, Andrey Gromov, Jonathan Gross, Bailey Gu, Alexander Jahn, Alexei Kitaev, Peter Kopietz, Gleb Kotoousov, Ashley Milsted, Olexei Motrunich, Sepehr Nezami, Kevin Slagle, Lev Spodyneiko, Michael Stone, Eugene Tang, Cenke Xu, Oleg Yevtushenko, Yi-Zhuang You, and Erez Zohar for valuable discussions. We gratefully acknowledge support from the Walter Burke Institute for Theoretical Physics at Caltech. The Institute for Quantum Information and Matter is an NSF Physics Frontiers Center. Contributions to this work by NIST, an agency of the US government, are not subject to US copyright. Any mention of commercial products does not indicate endorsement by NIST. V.V.A. thanks Olga Albert, Halina and Ryhor Kandratsenia, as well as Tatyana and Thomas Albert for providing daycare support throughout this work.\n\nSubmitted - 2111.12096.pdf
", "abstract": "Non-Abelian defects that bind Majorana or parafermion zero modes are prominent in several topological quantum computation schemes. Underpinning their established understanding is the quantum Ising spin chain, which can be recast as a fermionic model or viewed as a standalone effective theory for the surface-code edge -- both of which harbor non-Abelian defects. We generalize these notions by deriving an effective Ising-like spin chain describing the edge of quantum-double topological order. Relating Majorana and parafermion modes to anyonic strings, we introduce quantum-double generalizations of non-Abelian defects. We develop a way to embed finite-group valued qunits into those valued in continuous groups. Using this embedding, we provide a continuum description of the spin chain and recast its non-interacting part as a quantum wire via addition of a Wess-Zumino-Novikov-Witten term and non-Abelian bosonization.", "date": "2021-11-23", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220113-182244311", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220113-182244311", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.2111.12096", "primary_object": { "basename": "2111.12096.pdf", "url": "https://authors.library.caltech.edu/records/gnrr3-rdt94/files/2111.12096.pdf" }, "pub_year": "2021", "author_list": "Albert, Victor V.; Aasen, David; et el." }, { "id": "https://authors.library.caltech.edu/records/h9tr9-v6d33", "eprint_id": 112117, "eprint_status": "archive", "datestamp": "2023-08-20 05:55:04", "lastmod": "2023-10-23 20:54:30", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Chi-Fang", "name": { "family": "Chen", "given": "Chi-Fang" }, "orcid": "0000-0001-5589-7896" }, { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" } ] }, "title": "Concentration for Trotter error", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Yuan Su and Mario Berta for helpful discussions and Joel Tropp and Andrew Lucas for related collaborations. CFC is especially thankful for Joel Tropp for introducing to him the subject of matrix concentration inequalities. After this work was completed, we became aware of related work by Qi Zhao, You Zhou, Alexander F. Shaw, Tongyang Li, and Andrew M. Childs that also studies Hamiltonian simulation with random input states. We thank them for letting us know about their work. CFC is supported by Caltech RA fellowship and the Eddleman Fellowship.\n\nSubmitted - 2111.05324.pdf
", "abstract": "Quantum simulation is expected to be one of the key applications of future quantum computers. Product formulas, or Trotterization, are the oldest and, still today, an appealing method for quantum simulation. For an accurate product formula approximation in the spectral norm, the state-of-the-art gate complexity depends on the number of Hamiltonian terms and a certain 1-norm of its local terms. This work studies the concentration aspects of Trotter error: we prove that, typically, the Trotter error exhibits 2-norm (i.e., incoherent) scaling; the current estimate with 1-norm (i.e., coherent) scaling is for the worst cases. For k-local Hamiltonians and higher-order product formulas, we obtain gate count estimates for input states drawn from a 1-design ensemble (e.g., computational basis states). Our gate count depends on the number of Hamiltonian terms but replaces the 1-norm quantity by its analog in 2-norm, giving significant speedup for systems with large connectivity. Our results generalize to Hamiltonians with Fermionic terms and when the input state is drawn from a low-particle number subspace. Further, when the Hamiltonian itself has Gaussian coefficients (e.g., the SYK models), we show the stronger result that the 2-norm behavior persists even for the worst input state. Our main technical tool is a family of simple but versatile inequalities from non-commutative martingales called uniform smoothness. We use them to derive Hypercontractivity, namely p-norm estimates for low-degree polynomials, which implies concentration via Markov's inequality. In terms of optimality, we give examples that simultaneously match our p-norm bounds and the spectral norm bounds. Therefore, our improvement is due to asking a qualitatively different question from the spectral norm bounds. Our results give evidence that product formulas in practice may generically work much better than expected.", "date": "2021-11-09", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20211130-215806841", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211130-215806841", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Robert A. Millikan Fellowship" }, { "agency": "Eddleman Fellowship" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "AWS-Center-for-Quantum-Computing" } ] }, "doi": "10.48550/arXiv.2111.05324", "primary_object": { "basename": "2111.05324.pdf", "url": "https://authors.library.caltech.edu/records/h9tr9-v6d33/files/2111.05324.pdf" }, "pub_year": "2021", "author_list": "Chen, Chi-Fang and Brand\u00e3o, Fernando G. S. L." }, { "id": "https://authors.library.caltech.edu/records/d9pnk-zdh12", "eprint_id": 111235, "eprint_status": "archive", "datestamp": "2023-08-20 04:22:11", "lastmod": "2023-10-23 20:06:50", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Culf-Eric", "name": { "family": "Culf", "given": "Eric" } }, { "id": "Vidick-T", "name": { "family": "Vidick", "given": "Thomas" }, "orcid": "0000-0002-6405-365X" } ] }, "title": "A monogamy-of-entanglement game for subspace coset states", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution-ShareAlike 4.0 International (CC BY-SA 4.0). \n\nWe thank Fatih Kaleoglu for pointing out an error in an earlier proof of Lemma 3.4. E.C. would like to thank Anne Broadbent. E.C.'s work is supported by a CGS M scholarship from Canada's NSERC. T.V. is supported by NSF CAREER Grant CCF-1553477, AFOSR YIP award number FA9550-16-1-0495, MURI Grant FA9550-18-1-0161 and the IQIM, an NSF Physics Frontiers Center (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028).\n\nSubmitted - 2107.13324.pdf
", "abstract": "We establish a strong monogamy-of-entanglement property for subspace coset states, which are uniform superpositions of vectors in a linear subspace of F^n\u2082 to which has been applied a quantum one-time pad. This property was conjectured recently by [Coladangelo, Liu, Liu, and Zhandry, Crypto'21] and shown to have applications to unclonable decryption and copy-protection of pseudorandom functions. We present two proofs, one which directly follows the method of the original paper and the other which uses an observation from [Vidick and Zhang, Eurocrypt'20] to reduce the analysis to a simpler monogamy game based on BB'84 states. Both proofs ultimately rely on the same proof technique, introduced in [Tomamichel, Fehr, Kaniewski and Wehner, New Journal of Physics '13].", "date": "2021-10-06", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20211006-152638528", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211006-152638528", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "NSF", "grant_number": "CCF-1553477" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0495" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0161" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2107.13324", "primary_object": { "basename": "2107.13324.pdf", "url": "https://authors.library.caltech.edu/records/d9pnk-zdh12/files/2107.13324.pdf" }, "pub_year": "2021", "author_list": "Culf, Eric and Vidick, Thomas" }, { "id": "https://authors.library.caltech.edu/records/0vv01-b1807", "eprint_id": 112868, "eprint_status": "archive", "datestamp": "2023-08-20 04:41:42", "lastmod": "2023-10-23 22:49:20", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wampler-Matthew", "name": { "family": "Wampler", "given": "Matthew" } }, { "id": "Khor-Brian-J-J", "name": { "family": "Khor", "given": "Brian J. J." } }, { "id": "Refael-G", "name": { "family": "Refael", "given": "Gil" } }, { "id": "Klich-Israel", "name": { "family": "Klich", "given": "Israel" }, "orcid": "0000-0002-8979-0170" } ] }, "title": "Stirring by Staring: Measurement Induced Chirality", "ispublished": "unpub", "full_text_status": "public", "note": "I.K. would like to thank Kun-Woo Kim for discussions. The work of I.K., B.J.J.K. and M.W. was supported in part by the NSF grant DMR-1918207. G.R. acknowledges support from the Institute of Quantum Information and Matter, an NSF Physics Frontiers Center funded by the Gordon and Betty Moore Foundation, and the Simons Foundation, as well as to the NSF DMR grant number 1839271. This work was performed in part at Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611.\n\nSubmitted - 2108.05906.pdf
", "abstract": "Controlling the dynamics of quantum systems is a current frontier of quantum many-body physics. Recent advancements in experimental techniques suggest exciting new directions in drive-induced quantum states. Here, we present a simple scheme that relies solely on occupation measurements to induce a chiral quantum phase. Namely, we show that by utilizing a pattern of repeated quantum measurements we can produce chiral edge transport of fermions hopping on a Lieb lattice. We study in detail the dependence on measurement frequency, showing that in the Zeno limit the system can be described by a classical stochastic dynamics, yielding protected transport. As the frequency of measurements is reduced, the charge flow is reduced and vanishes when no measurements are done.", "date": "2021-08-12", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220113-182208459", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220113-182208459", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1918207" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Simons Foundation" }, { "agency": "NSF", "grant_number": "DMR-1839271" }, { "agency": "NSF", "grant_number": "PHY-1607611" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2108.05906", "primary_object": { "basename": "2108.05906.pdf", "url": "https://authors.library.caltech.edu/records/0vv01-b1807/files/2108.05906.pdf" }, "pub_year": "2021", "author_list": "Wampler, Matthew; Khor, Brian J. J.; et el." }, { "id": "https://authors.library.caltech.edu/records/8az1m-3ge11", "eprint_id": 110185, "eprint_status": "archive", "datestamp": "2023-08-20 02:43:53", "lastmod": "2023-10-23 18:20:19", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nezami-Sepehr", "name": { "family": "Nezami", "given": "Sepehr" } } ] }, "title": "Permanent of random matrices from representation theory: moments, numerics, concentration, and comments on hardness of boson-sampling", "ispublished": "unpub", "full_text_status": "public", "note": "The author would like to thank Scott Aaronson, Alex Arkhipov, David Gross, Nick Hunter-Jones, Richard Keung, Saeed Mehraban, Terence Tao, Van Vu, and MichaelWalter for illuminating discussions. The author is supported by the Walter Burke Institute for Theoretical Physics and IQIM at Caltech.\n\nSubmitted - 2104.06423.pdf
", "abstract": "Computing the distribution of permanents of random matrices has been an outstanding open problem for several decades. In quantum computing, \"anti-concentration\" of this distribution is an unproven input for the proof of hardness of the task of boson-sampling. We study permanents of random i.i.d. complex Gaussian matrices, and more broadly, submatrices of random unitary matrices. Using a hybrid representation-theoretic and combinatorial approach, we prove strong lower bounds for all moments of the permanent distribution. We provide substantial evidence that our bounds are close to being tight and constitute accurate estimates for the moments. Let U(d)^(k\u00d7k) be the distribution of k\u00d7k submatrices of d\u00d7d random unitary matrices, and Gk\u00d7k be the distribution of k\u00d7k complex Gaussian matrices. (1) Using the Schur-Weyl duality (or the Howe duality), we prove an expansion formula for the 2t-th moment of |Perm(M)| when M is drawn from U(d)^(k\u00d7k) or G^(k\u00d7k). (2) We prove a surprising size-moment duality: the 2t-th moment of the permanent of random k\u00d7k matrices is equal to the 2k-th moment of the permanent of t\u00d7t matrices. (3) We design an algorithm to exactly compute high moments of the permanent of small matrices. (4) We prove lower bounds for arbitrary moments of permanents of matrices drawn from G^(k\u00d7k) or U(k), and conjecture that our lower bounds are close to saturation up to a small multiplicative error. (5) Assuming our conjectures, we use the large deviation theory to compute the tail of the distribution of log-permanent of Gaussian matrices for the first time. (6) We argue that it is unlikely that the permanent distribution can be uniquely determined from the integer moments and one may need to supplement the moment calculations with extra assumptions to prove the anti-concentration conjecture.", "date": "2021-08-10", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20210809-220321102", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210809-220321102", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" } ] }, "local_group": { "items": [ { "id": "Walter-Burke-Institute-for-Theoretical-Physics" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2104.06423", "primary_object": { "basename": "2104.06423.pdf", "url": "https://authors.library.caltech.edu/records/8az1m-3ge11/files/2104.06423.pdf" }, "pub_year": "2021", "author_list": "Nezami, Sepehr" }, { "id": "https://authors.library.caltech.edu/records/gswrt-wgs31", "eprint_id": 110661, "eprint_status": "archive", "datestamp": "2023-08-20 04:37:56", "lastmod": "2023-10-23 19:47:32", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Pengfei-PHYSICS", "name": { "family": "Zhang", "given": "Pengfei" }, "orcid": "0000-0002-7408-0918" } ] }, "title": "Quantum Atomic Arrays: Fractional Filling and Trapping", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0) \n\nWe especially thank Yu Chen and Jianwen Jie for helpful discussions. P.Z. acknowledges support from the Walter Burke Institute for Theoretical Physics at Caltech.\n\nSubmitted - 2108.01153.pdf
", "abstract": "Quantum emitters, in particular, atomic arrays with subwavelength lattice constant, have been proposed to be an ideal platform for study the interplay between photons and electric dipoles. Previous theoretical studies are based on spin models, where each site is occupied by a point-like atom. In this work, motivated by the recent experiment [1], we develop a full quantum treatment using annihilation and creation operator of atoms in deep optical lattices. We use a diagrammatic approach on the Keldysh contour to derive the cooperative scattering of the light and obtain the general formula for the S matrix. We apply our formulism to study two effects beyond previous treatment with spin-operators, the effect of fractional filling and trapping. Both effects can lead to imperfectness of atomic mirrors. For the fractional filling case, we find the cooperative linewidth is linear in filling fraction n. When there is a mismatch between the trapping potentials for atoms in the ground state and the excited state, multiple resonances can appear in the response function. Our results are consistent with existing experiments.", "date": "2021-08-02", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20210831-203952905", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210831-203952905", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.2108.01153", "primary_object": { "basename": "2108.01153.pdf", "url": "https://authors.library.caltech.edu/records/gswrt-wgs31/files/2108.01153.pdf" }, "pub_year": "2021", "author_list": "Zhang, Pengfei" }, { "id": "https://authors.library.caltech.edu/records/d3hjb-yrc95", "eprint_id": 112703, "eprint_status": "archive", "datestamp": "2023-08-20 03:46:33", "lastmod": "2023-10-23 22:42:43", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Preskill-J", "name": { "family": "Preskill", "given": "John" }, "orcid": "0000-0002-2421-4762" } ] }, "title": "Quantum computing 40 years later", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nTo appear in Feynman Lectures on Computation, 2nd edition, published by Taylor & Francis Group, edited by Anthony J. G. Hey.\n\nSubmitted - 2106.10522.pdf
", "abstract": "Forty years ago, Richard Feynman proposed harnessing quantum physics to build a more powerful kind of computer. Realizing Feynman's vision is one of the grand challenges facing 21st century science and technology. In this article, we'll recall Feynman's contribution that launched the quest for a quantum computer, and assess where the field stands 40 years later.", "date": "2021-06-19", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220104-233143218", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220104-233143218", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" }, { "id": "AWS-Center-for-Quantum-Computing" } ] }, "doi": "10.48550/arXiv.2106.10522", "primary_object": { "basename": "2106.10522.pdf", "url": "https://authors.library.caltech.edu/records/d3hjb-yrc95/files/2106.10522.pdf" }, "pub_year": "2021", "author_list": "Preskill, John" }, { "id": "https://authors.library.caltech.edu/records/nq2dn-53e32", "eprint_id": 109096, "eprint_status": "archive", "datestamp": "2023-08-20 02:12:33", "lastmod": "2023-10-23 17:39:02", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Coller-Jordan-S", "name": { "family": "Cotler", "given": "Jordan S." } }, { "id": "Mark-Daniel-K", "name": { "family": "Mark", "given": "Daniel K." }, "orcid": "0000-0002-5017-5218" }, { "id": "Huang-Hsin-Yuan-Robert", "name": { "family": "Huang", "given": "Hsin-Yuan" }, "orcid": "0000-0001-5317-2613" }, { "id": "Hernandez-Felipe", "name": { "family": "Hernandez", "given": "Felipe" } }, { "id": "Choi-Joonhee", "name": { "family": "Choi", "given": "Joonhee" } }, { "id": "Shaw-Adam-L", "name": { "family": "Shaw", "given": "Adam L." }, "orcid": "0000-0002-8059-5950" }, { "id": "Endres-M", "name": { "family": "Endres", "given": "Manuel" }, "orcid": "0000-0002-4461-224X" }, { "id": "Choi-Soonwon", "name": { "family": "Choi", "given": "Soonwon" }, "orcid": "0000-0002-1247-062X" } ] }, "title": "Emergent quantum state designs from individual many-body wavefunctions", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Adam Bouland, Fernando Brand\u00e3o, Aram Harrow, Wen Wei Ho, Nicholas Hunter-Jones, Anand Natarajan, and Hannes Pichler for valuable discussions. This work was partly supported by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NSF Grant PHY-1733907), the NSF CAREER award (1753386), the AFOSR YIP (FA9550-19-1-0044), the DARPA ONISQ program (W911NF2010021), the Army Research Office MURI program (W911NF2010136), and the NSF QLCI program (2016245). JSC is supported by a Junior Fellowship from the Harvard Society of Fellows, as well as in part by the Department of Energy under grant DE-SC0007870. HH is supported by the J. Yang & Family Foundation. FH is supported by the Fannie & John Hertz Foundation. JC acknowledges support from the IQIM postdoctoral fellowship. ALS acknowledges support from the Eddleman Quantum graduate fellowship. SC acknowledges support from the Miller Institute for Basic Research in Science.\n\nSubmitted - 2103.03536.pdf
", "abstract": "Quantum chaos in many-body systems provides a bridge between statistical and quantum physics with strong predictive power. This framework is valuable for analyzing properties of complex quantum systems such as energy spectra and the dynamics of thermalization. While contemporary methods in quantum chaos often rely on random ensembles of quantum states and Hamiltonians, this is not reflective of most real-world systems. In this paper, we introduce a new perspective: across a wide range of examples, a single non-random quantum state is shown to encode universal and highly random quantum state ensembles. We characterize these ensembles using the notion of quantum state k-designs from quantum information theory and investigate their universality using a combination of analytic and numerical techniques. In particular, we establish that k-designs arise naturally from generic states as well as individual states associated with strongly interacting, time-independent Hamiltonian dynamics. Our results offer a new approach for studying quantum chaos and provide a practical method for sampling approximately uniformly random states; the latter has wide-ranging applications in quantum information science from tomography to benchmarking.", "date": "2021-05-12", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20210512-104037565", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210512-104037565", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1733907" }, { "agency": "NSF", "grant_number": "PHY-1753386" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-19-1-0044" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "W911NF2010021" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF2010136" }, { "agency": "NSF", "grant_number": "OMA-2016245" }, { "agency": "Harvard Society of Fellows" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0007870" }, { "agency": "J. Yang Family and Foundation" }, { "agency": "Fannie and John Hertz Foundation" }, { "agency": "Eddleman Quantum graduate fellowship" }, { "agency": "Miller Institute for Basic Research in Science" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2103.03536", "primary_object": { "basename": "2103.03536.pdf", "url": "https://authors.library.caltech.edu/records/nq2dn-53e32/files/2103.03536.pdf" }, "pub_year": "2021", "author_list": "Cotler, Jordan S.; Mark, Daniel K.; et el." }, { "id": "https://authors.library.caltech.edu/records/trrzm-8xw29", "eprint_id": 112702, "eprint_status": "archive", "datestamp": "2023-08-20 03:14:08", "lastmod": "2023-10-23 22:42:40", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Klocke-Kai", "name": { "family": "Klocke", "given": "Kai" }, "orcid": "0000-0002-9580-8509" }, { "id": "Moore-Joel-E", "name": { "family": "Moore", "given": "Joel E." } }, { "id": "Alicea-J", "name": { "family": "Alicea", "given": "Jason" }, "orcid": "0000-0001-9979-3423" }, { "id": "Hal\u00e1sz-G\u00e1bor-B", "name": { "family": "Hal\u00e1sz", "given": "G\u00e1bor B." } } ] }, "title": "Thermal anyon interferometry in phonon-coupled Kitaev spin liquids", "ispublished": "unpub", "full_text_status": "public", "note": "This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). \n\nWe thank Chengyun Hua and Alan Tennant for helpful discussions. This material is based upon work supported by the U.S. Department of Energy, Office of Science, National Quantum Information Science Research Centers, Quantum Science Center. J.A. additionally acknowledges support from the Army Research Office under Grant Award W911NF17-1-0323; the National Science Foundation through grant DMR-1723367; the Caltech Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation through Grant GBMF1250; and the Walter Burke Institute for Theoretical Physics at Caltech. J.E.M. acknowledges additional support from a Simons Investigatorship.\n\nSubmitted - 2105.05869.pdf
", "abstract": "Recent theoretical studies inspired by experiments on the Kitaev magnet \u03b1-RuCl\u2083 highlight the nontrivial impact of phonons on the thermal Hall conductivity of chiral topological phases. Here we introduce mixed mesoscopic-macroscopic devices that allow refined thermal-transport probes of non-Abelian spin liquids with Ising topological order. These devices feature a quantum-coherent mesoscopic region with negligible phonon conductance, flanked by macroscopic lobes that facilitate efficient thermalization between chiral Majorana edge modes and bulk phonons. We show that our devices enable (i) accurate determination of the quantized thermal Hall conductivity, (ii) identification of non-Abelian Ising anyons via the temperature dependence of the thermal conductance, and most interestingly (iii) single-anyon detection through heat-based anyon interferometry. Analogous results apply broadly to phonon-coupled chiral topological orders.", "date": "2021-05-12", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220104-233139832", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220104-233139832", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC05-00OR22725" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF17-1-0323" }, { "agency": "NSF", "grant_number": "DMR-1723367" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1250" }, { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" }, { "agency": "Simons Foundation" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.2105.05869", "primary_object": { "basename": "2105.05869.pdf", "url": "https://authors.library.caltech.edu/records/trrzm-8xw29/files/2105.05869.pdf" }, "pub_year": "2021", "author_list": "Klocke, Kai; Moore, Joel E.; et el." }, { "id": "https://authors.library.caltech.edu/records/gcbp1-s4w76", "eprint_id": 109092, "eprint_status": "archive", "datestamp": "2023-08-19 19:06:27", "lastmod": "2023-10-23 17:38:54", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" }, { "id": "Chemissany-Wissam", "name": { "family": "Chemissany", "given": "Wissam" }, "orcid": "0000-0002-9113-4463" }, { "id": "Hunter-Jones-Nicholas", "name": { "family": "Hunter-Jones", "given": "Nicholas" }, "orcid": "0000-0001-8578-1958" }, { "id": "Kueng-Richard-J", "name": { "family": "Kueng", "given": "Richard" } }, { "id": "Preskill-J", "name": { "family": "Preskill", "given": "John" }, "orcid": "0000-0002-2421-4762" } ] }, "title": "Models of quantum complexity growth", "ispublished": "unpub", "full_text_status": "public", "note": "The authors would like thank Dorit Aharonov, Thom Bohdanowicz, Elizabeth Crosson, Felix Haehl, Aram Harrow, Tomas Jochym-O'Connor, Hugo Marrochio, Grant Salton, Eugene Tang, and Thomas Vidick for inspiring discussions and valuable feedback. All authors acknowledge funding provided by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NSF Grant PHY-1733907). JP is supported in part by DOE Award DE-SC0018407 and by the Simons Foundation It from Qubit Collaboration. RK is supported in part by the Office of Naval Research (Award N00014-17-1-2146) and the Army Research Office (Award W911NF121054). NHJ would like to thank the IQIM at Caltech, McGill University, and UC Berkeley for their hospitality during the completion of this work. Research at Perimeter Institute is supported by the Government of Canada through the Department of Innovation, Science and Economic Development Canada and by the Province of Ontario through the Ministry of Research, Innovation and Science.\n\nSubmitted - 1912.04297.pdf
", "abstract": "The concept of quantum complexity has far-reaching implications spanning theoretical computer science, quantum many-body physics, and high energy physics. The quantum complexity of a unitary transformation or quantum state is defined as the size of the shortest quantum computation that executes the unitary or prepares the state. It is reasonable to expect that the complexity of a quantum state governed by a chaotic many-body Hamiltonian grows linearly with time for a time that is exponential in the system size; however, because it is hard to rule out a short-cut that improves the efficiency of a computation, it is notoriously difficult to derive lower bounds on quantum complexity for particular unitaries or states without making additional assumptions. To go further, one may study more generic models of complexity growth. We provide a rigorous connection between complexity growth and unitary k-designs, ensembles which capture the randomness of the unitary group. This connection allows us to leverage existing results about design growth to draw conclusions about the growth of complexity. We prove that local random quantum circuits generate unitary transformations whose complexity grows linearly for a long time, mirroring the behavior one expects in chaotic quantum systems and verifying conjectures by Brown and Susskind. Moreover, our results apply under a strong definition of quantum complexity based on optimal distinguishing measurements.", "date": "2021-05-12", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20210512-095238258", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210512-095238258", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1733907" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0018407" }, { "agency": "Simons Foundation" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-17-1-2146" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF121054" }, { "agency": "Perimeter Institute for Theoretical Physics" }, { "agency": "Department of Innovation, Science and Economic Development (Canada)" }, { "agency": "Ontario Ministry of Research, Innovation and Science" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.1912.04297", "primary_object": { "basename": "1912.04297.pdf", "url": "https://authors.library.caltech.edu/records/gcbp1-s4w76/files/1912.04297.pdf" }, "pub_year": "2021", "author_list": "Brand\u00e3o, Fernando G. S. L.; Chemissany, Wissam; et el." }, { "id": "https://authors.library.caltech.edu/records/dwtgm-d6e53", "eprint_id": 109085, "eprint_status": "archive", "datestamp": "2023-08-19 23:59:06", "lastmod": "2023-10-23 17:38:33", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Chi-Fang", "name": { "family": "Chen", "given": "Chi-Fang" }, "orcid": "0000-0001-5589-7896" }, { "id": "Kato-Kohtaro", "name": { "family": "Kato", "given": "Kohtaro" }, "orcid": "0000-0003-3317-2004" }, { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" } ] }, "title": "Matrix Product Density Operators: when do they have a local parent Hamiltonian?", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Jean-Francois Quint for comments on multiplicative ergodic theory. We thank Mario Berta,\nMarco Tomamichel, Hao-Chung Cheng for discussions about the DPI for CMI. CFC is thankful for\nPhysics TA Relief Fellowship and the Physics TA Fellowship at Caltech. KK acknowledges funding\nprovided by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NSF\nGrant PHY-1733907) and MEXT Quantum Leap Flagship Program (MEXT Q-LEAP) Grant Number\nJPMXS0120319794. FB acknowledges funding from NSF.\n\nSubmitted - 2010.14682.pdf
", "abstract": "We study whether one can write a Matrix Product Density Operator (MPDO) as the Gibbs state of a quasi-local parent Hamiltonian. We conjecture this is the case for generic MPDO and give supporting evidences. To investigate the locality of the parent Hamiltonian, we take the approach of checking whether the quantum conditional mutual information decays exponentially. The MPDO we consider are constructed from a chain of 1-input/2-output (`Y-shaped') completely-positive maps, i.e. the MPDO have a local purification. We derive an upper bound on the conditional mutual information for bistochastic channels and strictly positive channels, and show that it decays exponentially if the correctable algebra of the channel is trivial. We also introduce a conjecture on a quantum data processing inequality that implies the exponential decay of the conditional mutual information for every Y-shaped channel with trivial correctable algebra. We additionally investigate a close but nonequivalent cousin: MPDO measured in a local basis. We provide sufficient conditions for the exponential decay of the conditional mutual information of the measured states, and numerically confirmed they are generically true for certain random MPDO.", "date": "2021-05-11", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20210511-131755023", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210511-131755023", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1733907" }, { "agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)", "grant_number": "JPMXS0120319794" } ] }, "local_group": { "items": [ { "id": "AWS-Center-for-Quantum-Computing" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2010.14682", "primary_object": { "basename": "2010.14682.pdf", "url": "https://authors.library.caltech.edu/records/dwtgm-d6e53/files/2010.14682.pdf" }, "pub_year": "2021", "author_list": "Chen, Chi-Fang; Kato, Kohtaro; et el." }, { "id": "https://authors.library.caltech.edu/records/ycjk1-6sf86", "eprint_id": 109086, "eprint_status": "archive", "datestamp": "2023-08-19 23:24:35", "lastmod": "2023-10-23 17:38:35", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fran\u00e7a-Daniel-Stilck", "name": { "family": "Fran\u00e7a", "given": "Daniel Stilck" } }, { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" }, { "id": "Kueng-Richard-J", "name": { "family": "Kueng", "given": "Richard" } } ] }, "title": "Fast and robust quantum state tomography from few basis measurements", "ispublished": "unpub", "full_text_status": "public", "note": "We thank C. Ferrie, T. Grurl, C. Lancien, R. Konig and J.A.\nTropp for valuable input and helpful discussions. F.B. and R.K. acknowledge funding\nfrom the US National Science Foundation (PHY1733907). The Institute for Quantum\nInformation and Matter is an NSF Physics Frontiers Center. D.S.F. acknowledges financial\nsupport from VILLUM FONDEN via the QMATH Centre of Excellence (Grant no. 10059).\n\nData and code availability:\nSource data and code are available for this paper [Fra20].\nAll other data that support the plots within this paper and other findings of this study\nare available from the corresponding author upon reasonable request.\n\nSubmitted - 2009.08216.pdf
", "abstract": "Quantum state tomography is a powerful, but resource-intensive, general solution for numerous quantum information processing tasks. This motivates the design of robust tomography procedures that use relevant resources as sparingly as possible. Important cost factors include the number of state copies and measurement settings, as well as classical postprocessing time and memory. In this work, we present and analyze an online tomography algorithm designed to optimize all the aforementioned resources at the cost of a worse dependence on accuracy. The protocol is the first to give provably optimal performance in terms of rank and dimension for state copies, measurement settings and memory. Classical runtime is also reduced substantially and numerical experiments demonstrate a favorable comparison with other state-of-the-art techniques. Further improvements are possible by executing the algorithm on a quantum computer, giving a quantum speedup for quantum state tomography.", "date": "2021-05-11", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20210511-142009646", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210511-142009646", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-1733907" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Villum Fonden", "grant_number": "10059" } ] }, "local_group": { "items": [ { "id": "AWS-Center-for-Quantum-Computing" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2009.08216", "primary_object": { "basename": "2009.08216.pdf", "url": "https://authors.library.caltech.edu/records/ycjk1-6sf86/files/2009.08216.pdf" }, "pub_year": "2021", "author_list": "Fran\u00e7a, Daniel Stilck; Brand\u00e3o, Fernando G. S. L.; et el." }, { "id": "https://authors.library.caltech.edu/records/5krzh-per17", "eprint_id": 108662, "eprint_status": "archive", "datestamp": "2023-08-20 01:04:51", "lastmod": "2023-10-23 17:13:32", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Su-Yuan", "name": { "family": "Su", "given": "Yuan" }, "orcid": "0000-0003-1144-3563" }, { "id": "Huang-Hsin-Yuan-Robert", "name": { "family": "Huang", "given": "Hsin-Yuan" }, "orcid": "0000-0001-5317-2613" }, { "id": "Campbell-Earl-T", "name": { "family": "Campbell", "given": "Earl T." } } ] }, "title": "Nearly tight Trotterization of interacting electrons", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Fernando Brand\u02dcao for inspiring discussions during the initial stages of this work. YS\nthanks Nathan Wiebe, Guang Hao Low, Ryan Babbush, Minh Cong Tran, Kunal Sharma, John\nPreskill, and Andrew Childs for helpful discussions. He is supported by the National Science\nFoundation RAISE-TAQS 1839204 and Amazon Web Services, AWS Quantum Program. HH is\nsupported by the J. Yang & Family Foundation. The Institute for Quantum Information and\nMatter is an NSF Physics Frontiers Center PHY-1733907.\n\nSubmitted - 2012.09194.pdf
", "abstract": "We consider simulating quantum systems on digital quantum computers. We show that the performance of quantum simulation can be improved by simultaneously exploiting the commutativity of Hamiltonian, the sparsity of interactions, and the prior knowledge of initial state. We achieve this using Trotterization for a class of interacting electrons that encompasses various physical systems, including the plane-wave-basis electronic structure and the Fermi-Hubbard model. We estimate the simulation error by taking the transition amplitude of nested commutators of Hamiltonian terms within the \u03b7-electron manifold. We develop multiple techniques for bounding the transition amplitude and expectation of general fermionic operators, which may be of independent interest. We show that it suffices to use O(n^(5/3)/\u03b7^(2/3)+n^(4/3)\u03b7^(2/3)) gates to simulate electronic structure in the plane-wave basis with n spin orbitals and \u03b7 electrons up to a negligible factor, improving the best previous result in second quantization while outperforming the first-quantized simulation when n=O(\u03b7\u00b2). We also obtain an improvement for simulating the Fermi-Hubbard model. We construct concrete examples for which our bounds are almost saturated, giving a nearly tight Trotterization of interacting electrons.", "date": "2021-04-09", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20210408-131650720", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210408-131650720", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CCF-1839204" }, { "agency": "Amazon Web Services" }, { "agency": "J. Yang Family and Foundation" }, { "agency": "NSF", "grant_number": "PHY-1733907" } ] }, "local_group": { "items": [ { "id": "AWS-Center-for-Quantum-Computing" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2012.09194", "primary_object": { "basename": "2012.09194.pdf", "url": "https://authors.library.caltech.edu/records/5krzh-per17/files/2012.09194.pdf" }, "pub_year": "2021", "author_list": "Su, Yuan; Huang, Hsin-Yuan; et el." }, { "id": "https://authors.library.caltech.edu/records/jcrtb-1wq56", "eprint_id": 109101, "eprint_status": "archive", "datestamp": "2023-08-20 02:12:41", "lastmod": "2023-10-23 17:39:17", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Choi-Joonhee", "name": { "family": "Choi", "given": "Joonhee" }, "orcid": "0000-0002-3507-8751" }, { "id": "Shaw-Adam-L", "name": { "family": "Shaw", "given": "Adam L." }, "orcid": "0000-0002-8059-5950" }, { "id": "Madjarov-Ivaylo-S", "name": { "family": "Madjarov", "given": "Ivaylo S." } }, { "id": "Xie-Xin", "name": { "family": "Xie", "given": "Xin" }, "orcid": "0000-0003-4575-6103" }, { "id": "Covey-Jacob-P", "name": { "family": "Covey", "given": "Jacob P." }, "orcid": "0000-0001-5104-6883" }, { "id": "Coller-Jordan-S", "name": { "family": "Cotler", "given": "Jordan S." }, "orcid": "0000-0003-3161-9677" }, { "id": "Mark-Daniel-K", "name": { "family": "Mark", "given": "Daniel K." }, "orcid": "0000-0002-5017-5218" }, { "id": "Huang-Hsin-Yuan-Robert", "name": { "family": "Huang", "given": "Hsin-Yuan" }, "orcid": "0000-0001-5317-2613" }, { "id": "Kale-Anant", "name": { "family": "Kale", "given": "Anant" }, "orcid": "0000-0002-7049-5630" }, { "id": "Pichler-Hannes", "name": { "family": "Pichler", "given": "Hannes" }, "orcid": "0000-0003-2144-536X" }, { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" }, { "id": "Choi-Soonwon", "name": { "family": "Choi", "given": "Soonwon" }, "orcid": "0000-0002-1247-062X" }, { "id": "Endres-M", "name": { "family": "Endres", "given": "Manuel" }, "orcid": "0000-0002-4461-224X" } ] }, "title": "Emergent Quantum Randomness and Benchmarking from Hamiltonian Many-body Dynamics", "ispublished": "unpub", "full_text_status": "restricted", "note": "We acknowledge discussions with Abhinav Deshpande and Alexey Gorshkov as well as funding provided by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NSF Grant PHY-1733907), the NSF CAREER award (1753386), the AFOSR YIP (FA9550-19-1-0044), the DARPA ONISQ program (W911NF2010021), the Army Research Office MURI program (W911NF2010136), the NSF QLCI program (2016245), and Fred Blum. JC acknowledges support from the IQIM postdoctoral fellowship. ALS acknowledges support from the Eddleman Quantum graduate fellowship. JPC acknowledges support from the PMA Prize postdoctoral fellowship. HP acknowledges support by the Gordon and Betty Moore Foundation. HH is supported by the J. Yang & Family Foundation. AK acknowledges funding from the Harvard Quantum Initiative (HQI) graduate fellowship. JSC is supported by a Junior Fellowship from the Harvard Society of Fellows and the U.S. Department of Energy under grant Contract Number DE-SC0012567. SC acknowledges support from the Miller Institute for Basic Research in Science. \n\nJC and ALS contributed equally to this work.", "abstract": "Chaotic quantum many-body dynamics typically lead to relaxation of local observables. In this process, known as quantum thermalization, a subregion reaches a thermal state due to quantum correlations with the remainder of the system, which acts as an intrinsic bath. While the bath is generally assumed to be unobserved, modern quantum science experiments have the ability to track both subsystem and bath at a microscopic level. Here, by utilizing this ability, we discover that measurement results associated with small subsystems exhibit universal random statistics following chaotic quantum many-body dynamics, a phenomenon beyond the standard paradigm of quantum thermalization. We explain these observations with an ensemble of pure states, defined via correlations with the bath, that dynamically acquires a close to random distribution. Such random ensembles play an important role in quantum information science, associated with quantum supremacy tests and device verification, but typically require highly-engineered, time-dependent control for their preparation. In contrast, our approach uncovers random ensembles naturally emerging from evolution with a time-independent Hamiltonian. As an application of this emergent randomness, we develop a benchmarking protocol which estimates the many-body fidelity during generic chaotic evolution and demonstrate it using our Rydberg quantum simulator. Our work has wide ranging implications for the understanding of quantum many-body chaos and thermalization in terms of emergent randomness and at the same time paves the way for applications of this concept in a much wider context.", "date": "2021-03-05", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20210512-104054951", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210512-104054951", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1733907" }, { "agency": "NSF", "grant_number": "PHY-1753386" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-19-1-0044" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "W911NF2010021" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF2010136" }, { "agency": "NSF", "grant_number": "OMA-2016245" }, { "agency": "Fred Blum" }, { "agency": "Eddleman Quantum graduate fellowship" }, { "agency": "Caltech Division of Physics, Mathematics and Astronomy" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "J. Yang Family and Foundation" }, { "agency": "Harvard Quantum Initiative" }, { "agency": "Harvard Society of Fellows" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0012567" }, { "agency": "Miller Institute for Basic Research in Science" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2103.03535", "pub_year": "2021", "author_list": "Choi, Joonhee; Shaw, Adam L.; et el." }, { "id": "https://authors.library.caltech.edu/records/zkfxy-f6k81", "eprint_id": 105619, "eprint_status": "archive", "datestamp": "2023-08-19 23:15:48", "lastmod": "2023-10-20 22:11:23", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chaudhary-Swati", "name": { "family": "Chaudhary", "given": "Swati" } }, { "id": "Ron-Alon", "name": { "family": "Ron", "given": "Alon" } }, { "id": "Hsieh-David", "name": { "family": "Hsieh", "given": "David" }, "orcid": "0000-0002-0812-955X" }, { "id": "Refael-G", "name": { "family": "Refael", "given": "Gil" } } ] }, "title": "Controlling ligand-mediated exchange interactions in periodically driven magnetic materials", "ispublished": "unpub", "full_text_status": "public", "note": "We acknowledge support from the IQIM, an NSF Physics Frontiers Center funded through grant PHY-1733907. We are grateful for support from ARO MURI W911NF-16-1-0361 \"Quantum Materials by Design with Electromagnetic Excitation\" sponsored by the U.S. Army. GR is also grateful for support from the Simons Foundation and the Packard Foundation. AR is grateful for support from Zuckerman STEM leadership program.\n\nSubmitted - 2009.00813.pdf
", "abstract": "A periodic drive could alter the effective exchange interactions in magnetic materials. Here, we explore how exchange pathways affect the effective interactions of periodically driven magnetic materials. Aiming to apply Floquet engineering methods to two-dimensional magnetic materials, we consider realistic models and discuss the effect of a periodic drive on ligand-mediated exchange interactions. We show that depending on bond angles and the number of ligand ions involved in the exchange process, drive-induced changes can be very different from those calculated from direct-hopping models considered earlier. We study these effects and find that the presence of ligand ions must be taken into account, especially for TMTCs where ligand ion mediated next-neighbor interactions play a crucial role in determining the magnetic ground state of the system.", "date": "2020-09-28", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20200928-150652942", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200928-150652942", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1733907" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-16-1-0361" }, { "agency": "Simons Foundation" }, { "agency": "David and Lucile Packard Foundation" }, { "agency": "Zuckerman STEM Leadership Program" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2009.00813", "primary_object": { "basename": "2009.00813.pdf", "url": "https://authors.library.caltech.edu/records/zkfxy-f6k81/files/2009.00813.pdf" }, "pub_year": "2020", "author_list": "Chaudhary, Swati; Ron, Alon; et el." }, { "id": "https://authors.library.caltech.edu/records/pzwdd-r8g89", "eprint_id": 104615, "eprint_status": "archive", "datestamp": "2023-08-19 21:21:28", "lastmod": "2023-10-20 20:39:41", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Vidick-T", "name": { "family": "Vidick", "given": "Thomas" }, "orcid": "0000-0002-6405-365X" }, { "id": "Zhang-Tina", "name": { "family": "Zhang", "given": "Tina" } } ] }, "title": "Classical proofs of quantum knowledge", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Andru Gheorghiu for useful feedback. Thomas Vidick is supported by NSF CAREER Grant CCF-1553477, AFOSR YIP award number FA9550-16-1-0495, a CIFAR Azrieli Global Scholar award, MURI Grant FA9550-18-1-0161 and the IQIM, an NSF Physics Frontiers Center (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028).\n\nSubmitted - 2005.01691.pdf
", "abstract": "We define the notion of a proof of knowledge in the setting where the verifier is classical, but the prover is quantum, and where the witness that the prover holds is in general a quantum state. We establish simple properties of our definition, including that nondestructive classical proofs of quantum knowledge are impossible for nontrivial states, and that, under certain conditions on the parameters in our definition, a proof of knowledge protocol for a hard-to-clone state can be used as a (destructive) quantum money verification protocol. In addition, we provide two examples of protocols (both inspired by private-key classical verification protocols for quantum money schemes) which we can show to be proofs of quantum knowledge under our definition. In so doing, we introduce new techniques for the analysis of such protocols which build on results from the literature on nonlocal games. Finally, we show that, under our definition, the verification protocol introduced by Mahadev (FOCS 2018) is a classical argument of quantum knowledge for QMA relations.", "date": "2020-07-28", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20200728-145122122", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200728-145122122", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CCF-1553477" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0495" }, { "agency": "Canadian Institute for Advanced Research (CIFAR)" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0161" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2005.01691", "primary_object": { "basename": "2005.01691.pdf", "url": "https://authors.library.caltech.edu/records/pzwdd-r8g89/files/2005.01691.pdf" }, "pub_year": "2020", "author_list": "Vidick, Thomas and Zhang, Tina" }, { "id": "https://authors.library.caltech.edu/records/62xss-8sd56", "eprint_id": 103581, "eprint_status": "archive", "datestamp": "2023-08-22 04:41:48", "lastmod": "2023-10-20 16:30:52", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Pengfei", "name": { "family": "Zhang", "given": "Pengfei" }, "orcid": "0000-0002-4226-1394" } ] }, "title": "Universal subdiffusion in strongly tilted many-body systems", "ispublished": "unpub", "full_text_status": "public", "note": "We would like to thank Lei Pan for bringing our attention to the experiment [1].\n\nSubmitted - 2004.08695.pdf
", "abstract": "The quantum dynamics away from equilibrium is of fundamental interest for interacting many-body systems. In this letter, we study tilted many-body systems using the effective Hamiltonian derived from the microscopic description. We first give general arguments for the density relaxation rate satisfying 1/\u03c4\u221dk\u2074 for a large class of systems, including the Fermi Hubbard model case as observed in the the recent experiment [1]. Here k is the wave vector of the density wave. The main ingredients are the emergence of the reflection symmetry and dipole moment conservation to the leading non-trivial order of the large tilted strength. To support our analysis, we then construct a solvable model with large local Hilbert space dimension by coupling sites discribed by the Sachdev-Ye-Kitaev models, where the density response can be computed explicitly. The the tilt strength and the temperature dependence of the subdiffusion constant are also discussed.", "date": "2020-06-01", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20200601-095228090", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200601-095228090", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "primary_object": { "basename": "2004.08695.pdf", "url": "https://authors.library.caltech.edu/records/62xss-8sd56/files/2004.08695.pdf" }, "pub_year": "2020", "author_list": "Zhang, Pengfei" }, { "id": "https://authors.library.caltech.edu/records/7hyah-yr160", "eprint_id": 102607, "eprint_status": "archive", "datestamp": "2023-08-19 17:28:17", "lastmod": "2023-10-20 00:20:18", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lin-Joseph-X", "name": { "family": "Lin", "given": "Joseph X." } }, { "id": "Formaggio-J-A", "name": { "family": "Formaggio", "given": "Joseph A." } }, { "id": "Harrow-A-W", "name": { "family": "Harrow", "given": "Aram W." }, "orcid": "0000-0003-3220-7682" }, { "id": "Natarajan-A", "name": { "family": "Natarajan", "given": "Anand V." }, "orcid": "0000-0003-3648-3844" } ] }, "title": "Quantum Blackjack or Can MIT Bring Down the House Again?", "ispublished": "unpub", "full_text_status": "public", "note": "JXL acknowledges support from the MIT Undergraduate Research Opportunities Program (UROP). AWH was funded by NSF grants CCF-1452616, CCF-1729369, PHY-1818914 and ARO contract W911NF-17-1-0433. AVN was partially supported by NSF grant CCF-1452616. JAF is supported by U.S. Department of Energy Contract DE-SC0011091 and NSF award 1505678. JAF would also like to thank C. Pollak and his monthly \"Lonely Poker Hearts Club Band\" for the topic inspiration.\n\nSubmitted - 1908.09417.pdf
", "abstract": "We examine the advantages that quantum strategies afford in communication-limited games. Inspired by the card game blackjack, we focus on cooperative, two-party sequential games in which a single classical bit of communication is allowed from the player who moves first to the player who moves second. Within this setting, we explore the usage of quantum entanglement between the players and find analytic and numerical conditions for quantum advantage over classical strategies. Using these conditions, we study a family of blackjack-type games with varying numbers of card types, and find a range of parameters where quantum advantage is achieved. Furthermore, we give an explicit quantum circuit for the strategy achieving quantum advantage.", "date": "2020-04-17", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20200417-132554488", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200417-132554488", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Massachusetts Institute of Technology (MIT)" }, { "agency": "NSF", "grant_number": "CCF-1452616" }, { "agency": "NSF", "grant_number": "CCF-1729369" }, { "agency": "NSF", "grant_number": "PHY-1818914" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-17-1-0433" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0011091" }, { "agency": "NSF", "grant_number": "PHY-1505678" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1908.09417", "primary_object": { "basename": "1908.09417.pdf", "url": "https://authors.library.caltech.edu/records/7hyah-yr160/files/1908.09417.pdf" }, "pub_year": "2020", "author_list": "Lin, Joseph X.; Formaggio, Joseph A.; et el." }, { "id": "https://authors.library.caltech.edu/records/w7qxs-p6c29", "eprint_id": 102348, "eprint_status": "archive", "datestamp": "2023-08-19 20:03:43", "lastmod": "2023-10-20 00:07:22", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shirley-W-E", "name": { "family": "Shirley", "given": "Wilbur" } } ] }, "title": "Fractonic order and emergent fermionic gauge theory", "ispublished": "unpub", "full_text_status": "public", "note": "We are grateful to Xie Chen, Michael Hermele, Kevin Slagle, and Nathanan Tantivasadakarn for helpful discussions. The author is supported by the National Science Foundation under award number DMR-1654340 and the Institute for Quantum Information and Matter at Caltech.\n\nSubmitted - 2002.12026.pdf
", "abstract": "We consider fermionic systems in which fermion parity is conserved within rigid subsystems, and describe an explicit procedure for gauging such subsystem fermion parity symmetries to obtain bosonic spin Hamiltonians. We show that gauging planar or fractal subsystem fermion parity symmetry in three spatial dimensions gives rise to a plethora of exactly solvable spin models exhibiting novel gapped fractonic orders characterized by emergent fermionic gauge theory. The low energy excitations of these models include fractional quasiparticles with constrained mobility and emergent fermionic statistics. We illustrate this phenomenon through a series of examples including fermionic analogs of both foliated fracton phases and fractal spin liquids. We find that the foliated analogs actually exhibit the same fractonic order as their bosonic counterparts, while this is not generally the case for fermionic fractal spin liquids.", "date": "2020-04-06", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20200406-103524633", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200406-103524633", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1654340" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.2002.12026", "primary_object": { "basename": "2002.12026.pdf", "url": "https://authors.library.caltech.edu/records/w7qxs-p6c29/files/2002.12026.pdf" }, "pub_year": "2020", "author_list": "Shirley, Wilbur" }, { "id": "https://authors.library.caltech.edu/records/kx3az-ex716", "eprint_id": 101670, "eprint_status": "archive", "datestamp": "2023-08-19 19:37:54", "lastmod": "2023-10-19 22:56:40", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Haim-Arbel", "name": { "family": "Haim", "given": "Arbel" } }, { "id": "Kueng-R-J", "name": { "family": "Kueng", "given": "Richard" } }, { "id": "Refael-G", "name": { "family": "Refael", "given": "Gil" } } ] }, "title": "Variational-Correlations Approach to Quantum Many-body Problems", "ispublished": "unpub", "full_text_status": "public", "note": "We have benefited from discussions with Y. Baum, O. Motrunich, E. P. L. van Nieuwenburg, K. Slagel, and C. D. White. This research was supported by the Institute of Quantum Information and Matter, an NSF Frontier center funded by the Gordon and Betty Moore Foundation, the Packard Foundation, and the Simons foundation. AH acknowledges support from the Walter Burke Institute for Theoretical Physics at Caltech. RK acknowledges funding provided by the Office of Naval Research (Award N00014-17-1-2146) and the Army Research Office (Award W911NF121054).\n\nSubmitted - 2001.06510.pdf
", "abstract": "We investigate an approach for studying the ground state of a quantum many-body Hamiltonian that is based on treating the correlation functions as variational parameters. In this approach, the challenge set by the exponentially-large Hilbert space is circumvented by approximating the positivity of the density matrix, order-by-order, in a way that keeps track of a limited set of correlation functions. In particular, the density-matrix description is replaced by a correlation matrix whose dimension is kept linear in system size, to all orders of the approximation. Unlike the conventional variational principle which provides an upper bound on the ground-state energy, in this approach one obtains a lower bound instead. By treating several one-dimensional spin 1/2 Hamiltonians, we demonstrate the ability of this approach to produce long-range correlations, and a ground-state energy that converges to the exact result. Possible extensions, including to higher-excited states are discussed.", "date": "2020-03-03", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20200303-081122185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200303-081122185", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Institute of Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "David and Lucile Packard Foundation" }, { "agency": "Simons Foundation" }, { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-17-1-2146" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF121054" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.2001.06510", "primary_object": { "basename": "2001.06510.pdf", "url": "https://authors.library.caltech.edu/records/kx3az-ex716/files/2001.06510.pdf" }, "pub_year": "2020", "author_list": "Haim, Arbel; Kueng, Richard; et el." }, { "id": "https://authors.library.caltech.edu/records/grtv2-7wm63", "eprint_id": 100630, "eprint_status": "archive", "datestamp": "2023-08-19 18:46:44", "lastmod": "2023-10-18 21:41:14", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Coladangelo-A", "name": { "family": "Coladangelo", "given": "Andrea" } }, { "id": "Vidick-T", "name": { "family": "Vidick", "given": "Thomas" }, "orcid": "0000-0002-6405-365X" }, { "id": "Zhang-Tina", "name": { "family": "Zhang", "given": "Tina" } } ] }, "title": "Non-interactive zero-knowledge arguments for QMA, with preprocessing", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted - 1911.07546.pdf
", "abstract": "A non-interactive zero-knowledge (NIZK) proof system for a language L\u2208NP allows a prover (who is provided with an instance x\u2208L, and a witness w for x) to compute a classical certificate \u03c0 for the claim that x\u2208L such that \u03c0 has the following properties: 1) \u03c0 can be verified efficiently, and 2) \u03c0 does not reveal any information about w, besides the fact that it exists (i.e. that x\u2208L). NIZK proof systems have recently been shown to exist for all languages in NP in the common reference string (CRS) model and under the learning with errors (LWE) assumption.\nWe initiate the study of NIZK arguments for languages in QMA. Our first main result is the following: if LWE is hard for quantum computers, then any language in QMA has an NIZK argument with preprocessing. The preprocessing in our argument system consists of (i) the generation of a CRS and (ii) a single (instance-independent) quantum message from verifier to prover. The instance-dependent phase of our argument system involves only a single classical message from prover to verifier. Importantly, verification in our protocol is entirely classical, and the verifier needs not have quantum memory; its only quantum actions are in the preprocessing phase.\nOur second contribution is to extend the notion of a classical proof of knowledge to the quantum setting. We introduce the notions of arguments and proofs of quantum knowledge (AoQK/PoQK), and we show that our non-interactive argument system satisfies the definition of an AoQK. In particular, we explicitly construct an extractor which can recover a quantum witness from any prover who is successful in our protocol. We also show that any language in QMA has an (interactive) proof of quantum knowledge.", "date": "2020-01-11", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20200110-140701565", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200110-140701565", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1911.07546", "primary_object": { "basename": "1911.07546.pdf", "url": "https://authors.library.caltech.edu/records/grtv2-7wm63/files/1911.07546.pdf" }, "pub_year": "2020", "author_list": "Coladangelo, Andrea; Vidick, Thomas; et el." }, { "id": "https://authors.library.caltech.edu/records/9126p-wxk25", "eprint_id": 100353, "eprint_status": "archive", "datestamp": "2023-08-19 18:23:38", "lastmod": "2023-10-18 19:53:05", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Laurita-N-J", "name": { "family": "Laurita", "given": "N. J." } }, { "id": "Ron-Alon", "name": { "family": "Ron", "given": "A." }, "orcid": "0000-0002-1840-7824" }, { "id": "Han-J-W", "name": { "family": "Han", "given": "J. W." } }, { "id": "Scheie-A", "name": { "family": "Scheie", "given": "A." } }, { "id": "Sheckelton-J-P", "name": { "family": "Sheckelton", "given": "J. P." } }, { "id": "Smaha-R-W", "name": { "family": "Smaha", "given": "R. W." } }, { "id": "He-W", "name": { "family": "He", "given": "W." } }, { "id": "Wen-J-J", "name": { "family": "Wen", "given": "J.-J." } }, { "id": "Lee-J-S", "name": { "family": "Lee", "given": "J. S." } }, { "id": "Lee-Y-S", "name": { "family": "Lee", "given": "Y. S." } }, { "id": "Norman-M-R", "name": { "family": "Norman", "given": "M. R." }, "orcid": "0000-0002-9459-078X" }, { "id": "Hsieh-David", "name": { "family": "Hsieh", "given": "D." }, "orcid": "0000-0002-0812-955X" } ] }, "title": "Evidence for a Parity Broken Monoclinic Ground State in the S = 1/2 Kagom\u00e9 Antiferromagnet Herbertsmithite", "ispublished": "unpub", "full_text_status": "public", "note": "This work was supported by an ARO PECASE award W911NF-17-1-0204. D.H. also acknowledges support for instrumentation from the David and Lucile Packard Foundation and from the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (PHY-1733907). N.J.L. acknowledges partial support from the IQIM Postdoctoral Fellowship. M.R.N. was supported by the Materials Science and Engineering Division, Basic Energy Sciences, Office of Science, U.S. DOE. J.W.H. and J.S.L. acknowledge support from the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning under contract No. 2018R1A2B2005331. Crystal growth and characterization was performed at Stanford University and SLAC and was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract No. DE-AC02-76SF00515. Use of the Laue machine was supported through the Institute for Quantum Matter at Johns Hopkins University, by the U.S. Department of Energy, Division of Basic Energy Sciences, Grant DE-SC-0019331. A.S was supported through the Gordon and Betty Moore foundation under the EPIQS program GBMF4532. We thank H. Changlani, S. A. Kivelson, P. A. Lee, T. Senthil, and O. Tchernyshyov for helpful conversations. \n\nAuthor contributions: D.H., N.J.L and M.R.N conceived the experiment. N.J.L and A.R performed the non-linear harmonic generation measurements. J.W.H and J.S.L performed the ellipsometry measurements. A.S and N.J.L. performed the Laue diffraction measurements. J.P.S, R.W.S, W.H, J.J.W and Y.S.L prepared and characterized the sample. N.J.L and M.R.N analyzed the data. N.J.L, M.R.N, and D.H wrote the manuscript. \n\nThe authors declare no competing financial interests.\n\nSubmitted - 1910.13606.pdf
", "abstract": "Nearest-neighbor interacting S = 1/2 spins on the ideal Kagom\u00e9 lattice are predicted to form a variety of novel quantum entangled states, including quantum spin-liquid (SL) and valence bond solid (VBS) phases. In real materials, the presence of additional perturbative spin interactions may further expand the variety of entangled states, which recent theoretical analyses show are identifiable through the spontaneous loss of particular discrete point group symmetries. Here we comprehensively resolve the ground state point group symmetries of the prototypical Kagom\u00e9 SL candidate ZnCu\u2083(OH)\u2086Cl\u2082 (Herbertsmithite) using a combination of optical ellipsometry and wavelength-dependent multi-harmonic optical polarimetry. We uncover a subtle parity breaking monoclinic structural distortion at a temperature above the nearest-neighbor exchange energy scale. Surprisingly, the parity-breaking order parameter is dramatically enhanced upon cooling and closely tracks the build-up of nearest-neighbor spin correlations, suggesting that it is energetically favored by the SL state. The refined low temperature symmetry group greatly restricts the number of viable ground states, and, in the perturbative limit, points toward the formation of a nematic Z\u2082 striped SL ground state - a SL analogue of a liquid crystal.", "date": "2019-12-18", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20191218-130358489", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191218-130358489", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-17-1-0204" }, { "agency": "David and Lucile Packard Foundation" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1733907" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" }, { "agency": "National Research Foundation of Korea", "grant_number": "2018R1A2B2005331" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC-0019331" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF4532" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1910.13606", "primary_object": { "basename": "1910.13606.pdf", "url": "https://authors.library.caltech.edu/records/9126p-wxk25/files/1910.13606.pdf" }, "pub_year": "2019", "author_list": "Laurita, N. J.; Ron, A.; et el." }, { "id": "https://authors.library.caltech.edu/records/g6m6j-p0v87", "eprint_id": 97598, "eprint_status": "archive", "datestamp": "2023-08-19 05:34:20", "lastmod": "2023-10-18 16:07:42", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bohdanowicz-T-C", "name": { "family": "Bohdanowicz", "given": "Thomas C." } }, { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" } ] }, "title": "Universal Hamiltonians for Exponentially Long Simulation", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Dorit Aharonov for interesting discussions, Elizabeth Crosson for helpful discussions and suggestions, and Toby Cubitt for helpful comments on our first draft that lead us to correct several mistakes in our construction. Author T. B. acknowledges financial support from the National Science and Engineering Research Council of Canada (NSERC) in the form of a Postgraduate Scholarship (PGS-D) award during the time in which this work was completed.\n\nSubmitted - 1710.02625.pdf
", "abstract": "We construct a Hamiltonian whose dynamics simulate the dynamics of every other Hamiltonian up to exponentially long times in the system size. The Hamiltonian is time-independent, local, one-dimensional, and translation invariant. As a consequence, we show (under plausible computational complexity assumptions) that the circuit complexity of the unitary dynamics under this Hamiltonian grows steadily with time up to an exponential value in system size. This result makes progress on a recent conjecture by Susskind, in the context of the AdS/CFT correspondence, that the time evolution of the thermofield double state of two conformal fields theories with a holographic dual has a circuit complexity increasing linearly in time, up to exponential time.", "date": "2019-08-01", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20190801-134530640", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190801-134530640", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1710.02625", "primary_object": { "basename": "1710.02625.pdf", "url": "https://authors.library.caltech.edu/records/g6m6j-p0v87/files/1710.02625.pdf" }, "pub_year": "2019", "author_list": "Bohdanowicz, Thomas C. and Brand\u00e3o, Fernando G. S. L." }, { "id": "https://authors.library.caltech.edu/records/5yy13-10850", "eprint_id": 97597, "eprint_status": "archive", "datestamp": "2023-08-19 05:34:06", "lastmod": "2023-10-18 16:07:39", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" }, { "id": "Kalev-A", "name": { "family": "Kalev", "given": "Amir" } }, { "id": "Li-Tongyang", "name": { "family": "Li", "given": "Tongyang" } }, { "id": "Lin-Cedric-Yen-Yu", "name": { "family": "Lin", "given": "Cedric Yen-Yu" } }, { "id": "Svore-K-M", "name": { "family": "Svore", "given": "Krysta M." } }, { "id": "Wu-Xiaodi", "name": { "family": "Wu", "given": "Xiaodi" } } ] }, "title": "Quantum SDP Solvers: Large Speed-ups, Optimality, and Applications to Quantum Learning", "ispublished": "unpub", "full_text_status": "public", "keywords": "Quantum algorithms, Semidefinite program, Convex optimization", "note": "We thank Scott Aaronson, Joran van Apeldoorn, Andr\u00e1s Gily\u00e9n, Cupjin Huang, and anonymous reviewers for helpful discussions. We are also grateful to Joran van Apeldoorn and Andr\u00e1s Gily\u00e9n for sharing a working draft of [4] with us. FB was supported by NSF. CYL and AK are supported by the Department of Defense. TL is supported by NSF CCF-1526380. XW is supported by the U.S. Department of Energy, Office of Science, Office of Advanced Scientific Computing Research, Quantum Algorithms Teams program. XW is also supported by NSF grants CCF-1755800 and CCF-1816695.\n\nSubmitted - 1710.02581.pdf
", "abstract": "We give two quantum algorithms for solving semidefinite programs (SDPs) providing quantum speed-ups. We consider SDP instances with m constraint matrices, each of dimension n, rank at most r, and sparsity s. The first algorithm assumes access to an oracle to the matrices at unit cost. We show that it has run time \u00d5(s^2(\u221a((m\u03f5)^(\u221210)) + \u221a((n\u03f5)^(\u221212))), with \u03f5 the error of the solution. This gives an optimal dependence in terms of m, n and quadratic improvement over previous quantum algorithms when m \u2248 n. The second algorithm assumes a fully quantum input model in which the matrices are given as quantum states. We show that its run time is \u00d5 (\u221am + poly(r))\u22c5poly(log m,log n,B,\u03f5^(\u22121)), with B an upper bound on the trace-norm of all input matrices. In particular the complexity depends only poly-logarithmically in n and polynomially in r. \n\nWe apply the second SDP solver to learn a good description of a quantum state with respect to a set of measurements: Given m measurements and a supply of copies of an unknown state \u03c1 with rank at most r, we show we can find in time \u221am\u22c5poly(log m,log n,r,\u03f5^(\u22121)) a description of the state as a quantum circuit preparing a density matrix which has the same expectation values as \u03c1 on the m measurements, up to error \u03f5. The density matrix obtained is an approximation to the maximum entropy state consistent with the measurement data considered in Jaynes' principle from statistical mechanics. \n \nAs in previous work, we obtain our algorithm by \"quantizing\" classical SDP solvers based on the matrix multiplicative weight method. One of our main technical contributions is a quantum Gibbs state sampler for low-rank Hamiltonians with a poly-logarithmic dependence on its dimension, which could be of independent interest.", "date": "2019-08-01", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20190801-134527208", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190801-134527208", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CCF-1526380" }, { "agency": "Department of Defense" }, { "agency": "Department of Energy (DOE)" }, { "agency": "NSF", "grant_number": "CCF-1755800" }, { "agency": "NSF", "grant_number": "CCF-1816695" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1710.02581", "primary_object": { "basename": "1710.02581.pdf", "url": "https://authors.library.caltech.edu/records/5yy13-10850/files/1710.02581.pdf" }, "pub_year": "2019", "author_list": "Brand\u00e3o, Fernando G. S. L.; Kalev, Amir; et el." }, { "id": "https://authors.library.caltech.edu/records/2g3mx-htx93", "eprint_id": 97603, "eprint_status": "archive", "datestamp": "2023-08-19 16:44:41", "lastmod": "2023-10-18 16:07:52", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Morgan-Eric", "name": { "family": "Morgan", "given": "Eric" } }, { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" } ] }, "title": "A Classical Model Correspondence for G-symmetric Random Tensor Networks", "ispublished": "unpub", "full_text_status": "public", "note": "This work is part of IQIM, which is a National Science Foundation (NSF) Physics Frontiers Center (NSF Grant PHY-1733907).\n\nSubmitted - 1907.05490.pdf
", "abstract": "We consider the scaling of entanglement entropy in random Projected Entangled Pairs States (PEPS) with an internal symmetry given by a finite group G. We systematically demonstrate a correspondence between this entanglement entropy and the difference of free energies of a classical Ising model with an addition non-local term. This non-local term counts the number of domain walls in a particular configuration of the classical spin model. We argue that for that overwhelming majority of such states, this gives rise to an area law scaling with well-defined topological entanglement entropy. The topological entanglement entropy is shown to be log|G| for a simply connected region A and which manifests as a difference in the number of domain walls of ground state energies for the two spin models.", "date": "2019-08-01", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20190801-134548265", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190801-134548265", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-1733907" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1907.05490", "primary_object": { "basename": "1907.05490.pdf", "url": "https://authors.library.caltech.edu/records/2g3mx-htx93/files/1907.05490.pdf" }, "pub_year": "2019", "author_list": "Morgan, Eric and Brand\u00e3o, Fernando G. S. L." }, { "id": "https://authors.library.caltech.edu/records/9xhs3-nk939", "eprint_id": 97600, "eprint_status": "archive", "datestamp": "2023-08-19 13:14:58", "lastmod": "2023-10-18 16:07:46", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" }, { "id": "Broughton-M", "name": { "family": "Broughton", "given": "Michael" } }, { "id": "Farhi-E", "name": { "family": "Farhi", "given": "Edward" } }, { "id": "Gutmann-S", "name": { "family": "Gutmann", "given": "Sam" } }, { "id": "Neven-H", "name": { "family": "Neven", "given": "Hartmut" } } ] }, "title": "For Fixed Control Parameters the Quantum Approximate Optimization Algorithm's Objective Function Value Concentrates for Typical Instances", "ispublished": "unpub", "full_text_status": "public", "note": "We thank the Google AI Quantum team for useful discussion. EF also thanks Soonwon Choi, Misha Lukin, Hannes Pichler, Sheng-Tao Wang and Leo Zhou for many good chats. We acknowledge Jeffrey Goldstone for help with the acknowledgements. The work of EF was partially supported from NSF grant CCF-1729369 and ARO contract W911NF-17-1-0433.\n\nSubmitted - 1812.04170.pdf
", "abstract": "The Quantum Approximate Optimization Algorithm, QAOA, uses a shallow depth quantum circuit to produce a parameter dependent state. For a given combinatorial optimization problem instance, the quantum expectation of the associated cost function is the parameter dependent objective function of the QAOA. We demonstrate that if the parameters are fixed and the instance comes from a reasonable distribution then the objective function value is concentrated in the sense that typical instances have (nearly) the same value of the objective function. This applies not just for optimal parameters as the whole landscape is instance independent. We can prove this is true for low depth quantum circuits for instances of MaxCut on large 3-regular graphs. Our results generalize beyond this example. We support the arguments with numerical examples that show remarkable concentration. For higher depth circuits the numerics also show concentration and we argue for this using the Law of Large Numbers. We also observe by simulation that if we find parameters which result in good performance at say 10 bits these same parameters result in good performance at say 24 bits. These findings suggest ways to run the QAOA that reduce or eliminate the use of the outer loop optimization and may allow us to find good solutions with fewer calls to the quantum computer.", "date": "2019-08-01", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20190801-134537838", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190801-134537838", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CCF-1729369" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-17-1-0433" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1812.04170", "primary_object": { "basename": "1812.04170.pdf", "url": "https://authors.library.caltech.edu/records/9xhs3-nk939/files/1812.04170.pdf" }, "pub_year": "2019", "author_list": "Brand\u00e3o, Fernando G. S. L.; Broughton, Michael; et el." }, { "id": "https://authors.library.caltech.edu/records/xa9kx-m8439", "eprint_id": 93986, "eprint_status": "archive", "datestamp": "2023-08-20 13:26:32", "lastmod": "2023-10-20 17:34:48", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Vidick-T", "name": { "family": "Vidick", "given": "Thomas" }, "orcid": "0000-0002-6405-365X" }, { "id": "Yuen-Henry", "name": { "family": "Yuen", "given": "Henry" } } ] }, "title": "A simple proof of Renner's exponential de Finetti theorem", "ispublished": "unpub", "full_text_status": "public", "note": "Supported by NSF CAREER Grant CCF-1553477, an AFOSR YIP award, and the IQIM, an NSF Physics Frontiers Center (NFS Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028).\n\nSubmitted - 1608.04814.pdf
", "abstract": "We give a simple proof of the exponential de Finetti theorem due to Renner. Like Renner's proof, ours combines the post-selection de Finetti theorem, the Gentle Measurement lemma, and the Chernoff bound, but avoids virtually all calculations, including any use of the theory of types.", "date": "2019-03-20", "date_type": "published", "id_number": "CaltechAUTHORS:20190320-103022957", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190320-103022957", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CCF-1553477" }, { "agency": "Air Force Office of Scientific Research (AFOSR)" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1608.04814", "primary_object": { "basename": "1608.04814.pdf", "url": "https://authors.library.caltech.edu/records/xa9kx-m8439/files/1608.04814.pdf" }, "pub_year": "2019", "author_list": "Vidick, Thomas and Yuen, Henry" }, { "id": "https://authors.library.caltech.edu/records/xprn1-e3409", "eprint_id": 93985, "eprint_status": "archive", "datestamp": "2023-08-19 02:11:03", "lastmod": "2023-10-20 17:34:46", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Vidick-T", "name": { "family": "Vidick", "given": "Thomas" }, "orcid": "0000-0002-6405-365X" } ] }, "title": "Parallel DIQKD from parallel repetition", "ispublished": "unpub", "full_text_status": "public", "note": "Research funded by NSF CAREER Grant CCF-1553477, AFOSR YIP award number FA9550-16-1-0495, and the IQIM, an NSF Physics Frontiers Center (NFS Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028).\n\nSubmitted - 1703.08508.pdf
", "abstract": "We give an arguably simpler and more direct proof of a recent result by Miller, Jain and Shi, who proved device-independent security of a protocol for quantum key distribution in which the devices can be used in parallel. Our proof combines existing results on immunization (Kempe et al., SICOMP 2011) and parallel repetition (Bavarian et al., STOC 2017) of entangled games.", "date": "2019-03-20", "date_type": "published", "id_number": "CaltechAUTHORS:20190320-102806367", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190320-102806367", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CCF-1553477" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0495" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1703.08508", "primary_object": { "basename": "1703.08508.pdf", "url": "https://authors.library.caltech.edu/records/xprn1-e3409/files/1703.08508.pdf" }, "pub_year": "2019", "author_list": "Vidick, Thomas" }, { "id": "https://authors.library.caltech.edu/records/4709y-tha68", "eprint_id": 92795, "eprint_status": "archive", "datestamp": "2023-08-19 11:31:08", "lastmod": "2023-10-20 16:27:27", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Albert-V-V", "name": { "family": "Albert", "given": "Victor V." }, "orcid": "0000-0002-0335-9508" }, { "id": "Noh-Kyungjoo", "name": { "family": "Noh", "given": "Kyungjoo" }, "orcid": "0000-0002-6318-8472" }, { "id": "Reiter-F", "name": { "family": "Reiter", "given": "Florentin" } } ] }, "title": "Dissipative self-interference and robustness of continuous error-correction to miscalibration", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Mikhail D. Lukin, Jacob P. Covey, Richard\nKueng, John Preskill, Liang Jiang, Paola Cappellaro, and\nM\u02d8ad\u02d8alin Gu\u00b8t\u02d8a for illuminating discussions. We acknowledge\nfinancial support from theWalter Burke Institute for Theoretical\nPhysics at Caltech (V.V.A.), the Korea Foundation for Advanced\nStudies (K.N.), and a Feodor-Lynen fellowship from\nthe Alexander von Humboldt-Foundation (F.R.).\n\nSubmitted - 1809.07324.pdf
", "abstract": "We derive an effective equation of motion within the steady-state subspace of\na large family of Markovian open systems (i.e., Lindbladians) due to\nperturbations of their Hamiltonians and system-bath couplings. Under mild and\nrealistic conditions, competing dissipative processes destructively interfere\nwithout the need for fine-tuning and produce no dissipation within the\nsteady-state subspace. In quantum error-correction, these effects imply that\ncontinuously error-correcting Lindbladians are robust to calibration errors,\nincluding miscalibrations consisting of operators undetectable by the code. A\nsimilar interference is present in more general systems if one implements a\nparticular Hamiltonian drive, resulting in a coherent cancellation of\ndissipation. On the opposite extreme, we provide a simple implementation of\nuniversal Lindbladian simulation.", "date": "2019-02-15", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20190208-121222483", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190208-121222483", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" }, { "agency": "Korea Foundation for Advanced Studies" }, { "agency": "Alexander von Humboldt Foundation" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.1809.07324", "primary_object": { "basename": "1809.07324.pdf", "url": "https://authors.library.caltech.edu/records/4709y-tha68/files/1809.07324.pdf" }, "pub_year": "2019", "author_list": "Albert, Victor V.; Noh, Kyungjoo; et el." }, { "id": "https://authors.library.caltech.edu/records/2cqpy-dq195", "eprint_id": 92129, "eprint_status": "archive", "datestamp": "2023-08-19 11:34:41", "lastmod": "2023-10-19 23:59:54", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mirhosseini-M", "name": { "family": "Mirhosseini", "given": "Mohammad" }, "orcid": "0000-0002-9084-6880" }, { "id": "Kim-Eunjong", "name": { "family": "Kim", "given": "Eunjong" }, "orcid": "0000-0003-4879-8819" }, { "id": "Zhang-Xueyue", "name": { "family": "Zhang", "given": "Xueyue" }, "orcid": "0000-0001-8994-0629" }, { "id": "Sipahigil-Alp", "name": { "family": "Sipahigil", "given": "Alp" }, "orcid": "0000-0003-1469-5272" }, { "id": "Dieterle-Paul-B", "name": { "family": "Dieterle", "given": "Paul B." } }, { "id": "Keller-Andrew-J", "name": { "family": "Keller", "given": "Andrew J." }, "orcid": "0000-0003-3030-1149" }, { "id": "Asenjo-Garcia-Ana", "name": { "family": "Asenjo-Garcia", "given": "Ana" }, "orcid": "0000-0001-9850-5610" }, { "id": "Chang-Darrick-E", "name": { "family": "Chang", "given": "Darrick E." }, "orcid": "0000-0002-5426-7339" }, { "id": "Painter-O", "name": { "family": "Painter", "given": "Oskar" }, "orcid": "0000-0002-1581-9209" } ] }, "title": "Waveguide-mediated interaction of artificial atoms in the strong coupling regime", "ispublished": "unpub", "full_text_status": "public", "note": "The authors thank Jen-Hao Yeh and Ben Palmer for\nthe use of one of their cryogenic attenuators, critical\nto reducing thermal noise in the input waveguide line.\nThis work was supported by the AFOSR MURI Quantum\nPhotonic Matter (grant FA9550-16-1-0323), the Institute\nfor Quantum Information and Matter, an NSF\nPhysics Frontiers Center (grant PHY-1125565) with support\nof the Gordon and Betty Moore Foundation, and\nthe Kavli Nanoscience Institute at Caltech. D.E.C. acknowledges\nsupport from the ERC Starting Grant FOQAL,\nMINECO Plan Nacional Grant CANS, MINECO\nSevero Ochoa Grant No. SEV-2015-0522, CERCA Programme/\nGeneralitat de Catalunya, and Fundacio Privada.\nM.M. is supported through a KNI Postdoctoral\nFellowship, A.J.K. and A.S. are supported by IQIM Postdoctoral\nScholarships, P.B.D. is supported by a Hertz Graduate Fellowship Award, and A.A.-G. is supported by the Global Marie Curie Fellowship under the LANTERN\nprogram.\n\nSubmitted - 1809.09752.pdf
", "abstract": "Waveguide quantum electrodynamics studies photon-mediated interactions of quantum emitters in a one-dimensional radiation channel. Although signatures of such interactions have been observed previously in a variety of physical systems, observation of coherent cooperative dynamics has been obscured by radiative decay of atoms into the waveguide. Employing transmon qubits as artificial atoms coupled to a microwave coplanar waveguide, here we observe dynamical oscillations in an open system where a designated probe qubit interacts with an entangled dark state of an array of qubits which effectively traps radiation as an atomic cavity. The qubit-cavity system is shown to achieve a large cooperativity of C=172 due to collective enhancement of photon-mediated interactions, entering the strong coupling regime. The quantum coherence of the dark state cavity is also explored through its nonlinear response at the single-excitation level. With realistic refinements, this system is suitable for studying the many-body dynamics of large (N>10) quantum spin chains, synthesizing highly non-classical radiation fields on demand, and implementing universal quantum logic operations with high fidelity on information encoded within decoherence-free subspaces.", "date": "2019-01-08", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20190108-091005866", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190108-091005866", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0323" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "European Research Council (ERC)", "grant_number": "FOQAL" }, { "agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)", "grant_number": "CANS" }, { "agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)", "grant_number": "SEV-2015-0522" }, { "agency": "Generalitat de Catalunya" }, { "agency": "Fundacio Privada" }, { "agency": "Fannie and John Hertz Foundation" }, { "agency": "Marie Curie Fellowship" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.48550/arXiv.1809.09752", "primary_object": { "basename": "1809.09752.pdf", "url": "https://authors.library.caltech.edu/records/2cqpy-dq195/files/1809.09752.pdf" }, "pub_year": "2019", "author_list": "Mirhosseini, Mohammad; Kim, Eunjong; et el." }, { "id": "https://authors.library.caltech.edu/records/d7bgb-4sf23", "eprint_id": 90637, "eprint_status": "archive", "datestamp": "2023-08-19 11:30:15", "lastmod": "2023-10-19 14:42:14", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Haim-Arbel", "name": { "family": "Haim", "given": "Arbel" } }, { "id": "Oreg-Y", "name": { "family": "Oreg", "given": "Yuval" } } ] }, "title": "Time-reversal-invariant topological superconductivity", "ispublished": "unpub", "full_text_status": "public", "keywords": "Topological Superconductivity, Topological states of matter, time-reversal symmetry, Majorana zero modes, Proximity effect", "note": "Our research of time-reversal-invariant topological superconductivity was conducted in collaboration\nwith E. Berg, K. Flensberg, A Keselman, and K. W\u00f6lms. We have also benefited from discussions with I.\nC. Fulga, C. M. Marcus, K. Michaeli, F. von Oppen, M.-T. Rieder, Y. Schattner, E. Sela and A. Stern. A.\nH acknowledges support from the Walter Burke Institute for theoretical physics at Caltech. Y. O. acknowledges\nsupport from the Israeli Science Foundation (ISF), the Minerva Foundation, the Binational Science\nFoundation (BSF), and the European Research Council under the European Union's Seventh Framework\nProgramme (FP7/2007-2013)/ERC Grant agreement MUNATOP No. 340210.\n\nSubmitted - 1809.06863.pdf
", "abstract": "A topological superconductor is characterized by having a pairing gap in the bulk and gapless self-hermitian Majorana modes at its boundary. In one dimension, these are zero-energy modes bound to the ends, while in two dimensions these are chiral gapless modes traveling along the edge. Majorana modes have attracted a lot of interest due to their exotic properties, which include non-abelian exchange statistics. Progress in realizing topological superconductivity has been made by combining spin-orbit coupling, conventional superconductivity, and magnetism. The existence of protected Majorana modes, however, does not inherently require the breaking of time-reversal symmetry by magnetic fields. Indeed, pairs of Majorana modes can reside at the boundary of a \\emph{time-reversal-invariant} topological superconductor (TRITOPS). It is the time-reversal symmetry which then protects this so-called Majorana Kramers' pair from gapping out. This is analogous to the case of the two-dimensional topological insulator, with its pair of helical gapless boundary modes, protected by time-reversal symmetry. Realizing the TRITOPS phase will be a major step in the study of topological phases of matter. In this paper we describe the physical properties of the TRITOPS phase, and review recent proposals for engineering and detecting them in condensed matter systems, in one and two spatial dimensions. We mostly focus on extrinsic superconductors, where superconductivity is introduced through the proximity effect. We emphasize the role of interplay between attractive and repulsive electron-electron interaction as an underlying mechanism. When discussing the detection of the TRITOPS phase, we focus on the physical imprint of Majorana Kramers' pairs, and review proposals of transport measurement which can reveal their existence.", "date": "2018-11-06", "date_type": "published", "id_number": "CaltechAUTHORS:20181105-101425533", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181105-101425533", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" }, { "agency": "Israel Science Foundation" }, { "agency": "Minerva Foundation" }, { "agency": "Binational Science Foundation (USA-Israel)" }, { "agency": "European Research Council (ERC)", "grant_number": "340210" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.1809.06863", "primary_object": { "basename": "1809.06863.pdf", "url": "https://authors.library.caltech.edu/records/d7bgb-4sf23/files/1809.06863.pdf" }, "pub_year": "2018", "author_list": "Haim, Arbel and Oreg, Yuval" }, { "id": "https://authors.library.caltech.edu/records/k8jna-34a79", "eprint_id": 83091, "eprint_status": "archive", "datestamp": "2023-08-19 00:02:47", "lastmod": "2023-10-17 22:54:25", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Delfosse-N", "name": { "family": "Delfosse", "given": "Nicolas" }, "orcid": "0000-0002-3949-981X" }, { "id": "Iyer-P", "name": { "family": "Iyer", "given": "Pavithran" } }, { "id": "Poulin-D", "name": { "family": "Poulin", "given": "David" } } ] }, "title": "A linear-time benchmarking tool for generalized surface codes", "ispublished": "unpub", "full_text_status": "public", "note": "The authors would like to thank Marcus da Silva for enlighting discussions and Mario Berta and Tomas Jochym-O'Connor for their comments on a preliminary version of our software. ND acknowledges funding provided by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-2644). This work was supported by the Army Research Office contract number W911NF-14-C-0048. PI and DP are supported by Canada's NSERC and by the Canadian Institute for Advanced Research.\n\nSubmitted - 1611.04256.pdf
", "abstract": "Quantum information processors need to be protected against errors and faults. One of the most widely considered fault-tolerant architecture is based on surface codes. While the general principles of these codes are well understood and basic code properties such as minimum distance and rate are easy to characterize, a code's average performance depends on the detailed geometric layout of the qubits. To date, optimizing a surface code architecture and comparing different geometric layouts relies on costly numerical simulations. Here, we propose a benchmarking algorithm for simulating the performance of surface codes, and generalizations thereof, that runs in linear time. We\nimplemented this algorithm in a software that generates performance reports and allows to quickly compare different architectures.", "date": "2017-11-14", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20171108-153922644", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171108-153922644", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-2644" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-14-C-0048" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Canadian Institute for Advanced Research (CIFAR)" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1611.04256", "primary_object": { "basename": "1611.04256.pdf", "url": "https://authors.library.caltech.edu/records/k8jna-34a79/files/1611.04256.pdf" }, "pub_year": "2017", "author_list": "Delfosse, Nicolas; Iyer, Pavithran; et el." }, { "id": "https://authors.library.caltech.edu/records/cb5v6-0mb36", "eprint_id": 83111, "eprint_status": "archive", "datestamp": "2023-08-20 12:26:56", "lastmod": "2023-10-17 22:55:01", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Delfosse-N", "name": { "family": "Delfosse", "given": "Nicolas" }, "orcid": "0000-0002-3949-981X" }, { "id": "Iyer-P", "name": { "family": "Iyer", "given": "Pavithran" } }, { "id": "Poulin-D", "name": { "family": "Poulin", "given": "David" } } ] }, "title": "Generalized surface codes and packing of logical qubits", "ispublished": "unpub", "full_text_status": "public", "note": "The authors would like to thank Aleksander Kubica and Fernando\nPastawski for their comments on a preliminary version of this article.\nND was supported by the U.S. Army Research Office under Grant No. W911NF-14-1-0272 and by the NSF under Grant No. PHY-1416578, ND acknowledges funding provided by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-2644). PI and DP were supported by Canada's NSERC and by the Canadian Institute for Advanced Research.\n\nSubmitted - 1606.07116.pdf
", "abstract": "We consider a notion of relative homology (and cohomology) for surfaces with two types of boundaries. Using this tool, we study a generalization of Kitaev's code based on surfaces with mixed boundaries. This construction includes both Bravyi and Kitaev's and Freedman and Meyer's extension of Kitaev's toric code. We argue that our generalization offers a denser storage of quantum information. In a planar architecture, we obtain a three-fold overhead reduction over the standard architecture consisting of a punctured square lattice.", "date": "2017-11-14", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20171109-142607199", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171109-142607199", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-14-1-0272" }, { "agency": "NSF", "grant_number": "PHY-1416578" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-2644" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Canadian Institute for Advanced Research (CIFAR)" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1606.07116", "primary_object": { "basename": "1606.07116.pdf", "url": "https://authors.library.caltech.edu/records/cb5v6-0mb36/files/1606.07116.pdf" }, "pub_year": "2017", "author_list": "Delfosse, Nicolas; Iyer, Pavithran; et el." }, { "id": "https://authors.library.caltech.edu/records/jdynz-kjd13", "eprint_id": 82949, "eprint_status": "archive", "datestamp": "2023-08-19 04:46:20", "lastmod": "2023-10-17 22:47:49", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mozgunv-E", "name": { "family": "Mozgunov", "given": "Evgeny" } } ] }, "title": "Area law in the exact solution of many-body localized systems", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted - 1708.08069.pdf
", "abstract": "Many-body localization was proven under realistic assumptions by constructing a quasi-local unitary rotation that diagonalizes the Hamiltonian (Imbrie, 2016). A natural generalization is to consider all unitaries that have a\nsimilar structure. We bound entanglement for states generated by such unitaries, thus providing an independent proof of area law in eigenstates of many-body localized systems. An error of approximating the unitary by a\nfinite-depth local circuit is obtained. We connect the defined family of unitaries to other results about many-body localization (Kim et al, 2014), in particular Lieb-Robinson bound. Finally we argue that any Hamiltonian can be\ndiagonalized by such a unitary, given it has a slow enough logarithmic lightcone in its Lieb-Robinson bound.", "date": "2017-11-03", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20171103-150936253", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171103-150936253", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1708.08069", "primary_object": { "basename": "1708.08069.pdf", "url": "https://authors.library.caltech.edu/records/jdynz-kjd13/files/1708.08069.pdf" }, "pub_year": "2017", "author_list": "Mozgunov, Evgeny" }, { "id": "https://authors.library.caltech.edu/records/31ge0-1xk43", "eprint_id": 82954, "eprint_status": "archive", "datestamp": "2023-08-19 00:02:24", "lastmod": "2023-10-17 22:48:08", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mozgunv-E", "name": { "family": "Mozgunov", "given": "Evgeny" } } ] }, "title": "Local Master Equation for Small Temperatures", "ispublished": "unpub", "full_text_status": "public", "note": "The author is thankful to Alexei Kitaev, John Preskill\nand Leonid Pryadko for useful comments and discussion.\n\nSubmitted - 1611.04188.pdf
", "abstract": "We present a local Master equation for open system dynamics in two forms:Markovian and non-Markovian. Both have a wider range of validity than the Lindblad equation investigated by Davies. For low temperatures, they do not require coupling to be exponentially weak in the system size. If the state remains a low bond dimension Matrix Product State throughout the evolution, the local equation can be simulated in time polynomial in system size.", "date": "2017-11-03", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20171103-153609085", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171103-153609085", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1611.04188", "primary_object": { "basename": "1611.04188.pdf", "url": "https://authors.library.caltech.edu/records/31ge0-1xk43/files/1611.04188.pdf" }, "pub_year": "2017", "author_list": "Mozgunov, Evgeny" }, { "id": "https://authors.library.caltech.edu/records/4f48k-24980", "eprint_id": 82896, "eprint_status": "archive", "datestamp": "2023-08-19 02:12:16", "lastmod": "2023-10-17 22:45:26", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Crosson-E", "name": { "family": "Crosson", "given": "Elizabeth" } }, { "id": "Bowen-J", "name": { "family": "Bowen", "given": "John" } } ] }, "title": "Quantum ground state isoperimetric inequalities for the energy spectrum of local Hamiltonians", "ispublished": "unpub", "full_text_status": "public", "note": "E. C. is grateful for support provided by the Institute for\nQuantum Information and Matter, an NSF Physics Frontiers Center (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028).\nJ.B. is grateful for support provided by the Caltech Summer Undergraduate Research Fellowship program, and also thanks the IQIM for hospitality.\n\nSubmitted - 1703.10133.pdf
", "abstract": "We investigate the relationship between the energy spectrum of a local Hamiltonian and the geometric properties of its ground state. By generalizing a standard framework from the analysis of Markov chains to arbitrary\n(non-stoquastic) Hamiltonians we are naturally led to see that the spectral gap can always be upper bounded by an isoperimetric ratio that depends only on the ground state probability distribution and the range of the terms in the\nHamiltonian, but not on any other details of the interaction couplings. This means that for a given probability distribution the inequality constrains the\nspectral gap of any local Hamiltonian with this distribution as its ground state probability distribution in some basis (Eldar and Harrow derived a similar result [1] in order to characterize the output of low-depth quantum\ncircuits). Going further, we relate the Hilbert space localization properties of the ground state to higher energy eigenvalues by showing that the presence\nof k strongly localized ground state modes (i.e. clusters of probability, or subsets with small expansion) in Hilbert space implies the presence of k energy eigenvalues that are close to the ground state energy. Our results suggest that\nquantum adiabatic optimization using local Hamiltonians will inevitably encounter small spectral gaps when attempting to prepare ground states corresponding to multi-modal probability distributions with strongly localized\nmodes, and this problem cannot necessarily be alleviated with the inclusion of non-stoquastic couplings.", "date": "2017-11-02", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20171102-115811858", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171102-115811858", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" } ] }, "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "IQIM", "value": "Institute for Quantum Information and Matter" } ] }, "doi": "10.48550/arXiv.1703.10133", "primary_object": { "basename": "1703.10133.pdf", "url": "https://authors.library.caltech.edu/records/4f48k-24980/files/1703.10133.pdf" }, "pub_year": "2017", "author_list": "Crosson, Elizabeth and Bowen, John" }, { "id": "https://authors.library.caltech.edu/records/dtdq5-r8r46", "eprint_id": 79370, "eprint_status": "archive", "datestamp": "2023-08-19 02:40:49", "lastmod": "2023-10-26 16:09:24", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brand\u00e3o-F-G-S-L", "name": { "family": "Brand\u00e3o", "given": "Fernando G. S. L." }, "orcid": "0000-0003-3866-9378" }, { "id": "Svore-K-M", "name": { "family": "Svore", "given": "Krysta M." } } ] }, "title": "Quantum Speed-ups for Semidefinite Programming", "ispublished": "unpub", "full_text_status": "public", "note": "(Submitted on 18 Sep 2016 (v1), last revised 20 Apr 2017 (this version, v4)) \n\nWe thank Joran van Apeldoorn, Ronald de Wolf, Andras Gilyen, Aram Harrow, Sander Gribling, Matt Hastings, Cedric Yen-Yu Lin, Ojas Parekh, and David Poulin for interesting discussions and useful comments on the paper.\n\nSubmitted - 1609.05537.pdf
", "abstract": "We give a quantum algorithm for solving semidefinite programs (SDPs). It has worst case running time n^(1/2)m^(1/2)S^2 poly(log(n), log(m), R, r, 1/\u03b4), with n and s the dimension and sparsity of the input matrices, respectively, m the number of constraints, \u03b4 the accuracy of the solution, and R, r upper bounds on the size of the optimal primal and dual solutions. This gives a square-root unconditional speed-up over any classical method for solving SDPs both in n and m. We prove the algorithm cannot be substantially improved giving a \u03a9(n^(1/2) + m^(1/2)) quantum lower bound for solving semidefinite programs with constant s, R, r and \u03b4. \n\nWe then argue that in some instances the algorithm offer even exponential speed-ups. This is the case whenever the quantum Gibbs states of Hamiltonians given by linear combinations of the input matrices of the SDP can be prepared efficiently on a quantum computer. An example are SDPs in which the input matrices have low-rank: For SDPs with the maximum rank of any input matrix bounded by rank, we show the quantum algorithm runs in time poly(log(n), log(m), rank, r, R, \u03b4)m^(1/2). \n\nThe quantum algorithm is constructed by a combination of quantum Gibbs sampling and the multiplicative weight method. In particular it is based on an classical algorithm of Arora and Kale for approximately solving SDPs. We present a modification of their algorithm to eliminate the need of solving an inner linear program which may be of independent interest.", "date": "2017-07-26", "date_type": "published", "id_number": "CaltechAUTHORS:20170726-063707920", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170726-063707920", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1609.05537", "primary_object": { "basename": "1609.05537.pdf", "url": "https://authors.library.caltech.edu/records/dtdq5-r8r46/files/1609.05537.pdf" }, "pub_year": "2017", "author_list": "Brand\u00e3o, Fernando G. S. L. and Svore, Krysta M." }, { "id": "https://authors.library.caltech.edu/records/64pbm-5kq54", "eprint_id": 79097, "eprint_status": "archive", "datestamp": "2023-08-19 04:07:28", "lastmod": "2023-10-26 14:35:29", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chun-Sungbong", "name": { "family": "Chun", "given": "Sungbong" } }, { "id": "Bao-Ning", "name": { "family": "Bao", "given": "Ning" }, "orcid": "0000-0002-3296-1039" } ] }, "title": "Entanglement entropy from SU(2) Chern-Simons theory and symmetric webs", "ispublished": "unpub", "full_text_status": "public", "note": "We would like to thank Fran\u00b8cois Costantino, Sergei Gukov, Peter Kravchuck, Greg Kuperberg,\nand Onkar Parrikar for discussions. N.B. is funded as a Burke Fellow at the Walter\nBurke Institute for Theoretical Physics. The work is funded in part by the DOE Grant DESC0011632\nand the Walter Burke Institute for Theoretical Physics, and also by the Samsung\nScholarship.\n\nSubmitted - 1707.03525.pdf
", "abstract": "A path integral on a link complement of a three-sphere fixes a vector (the\n\"link state\") in Chern-Simons theory. The link state can be written in a\ncertain basis with the colored link invariants as its coefficients. We use\nsymmetric webs to systematically compute the colored link invariants, by which\nwe can write down the multi-partite entangled state of any given link. It is\nstill unknown if a product state necessarily implies that the corresponding\ncomponents are unlinked, and we leave it as a conjecture.", "date": "2017-07-14", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20170713-145329116", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170713-145329116", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0011632" }, { "agency": "Samsung Scholarship" }, { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" } ] }, "other_numbering_system": { "items": [ { "id": "2017-035", "name": "CALT-TH" } ] }, "local_group": { "items": [ { "id": "Walter-Burke-Institute-for-Theoretical-Physics" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1707.03525", "primary_object": { "basename": "1707.03525.pdf", "url": "https://authors.library.caltech.edu/records/64pbm-5kq54/files/1707.03525.pdf" }, "pub_year": "2017", "author_list": "Chun, Sungbong and Bao, Ning" }, { "id": "https://authors.library.caltech.edu/records/c71hk-tp411", "eprint_id": 77957, "eprint_status": "archive", "datestamp": "2023-08-19 00:58:34", "lastmod": "2023-10-25 23:36:18", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Yichen", "name": { "family": "Huang", "given": "Yichen" } } ] }, "title": "Is microcanonical ensemble stable?", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted on 2 Jan 2017. \n\nThe author would like to thank John Preskill for an insightful comment. \n\nWe acknowledge funding provided by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-2644).\n\nSubmitted - 1701.00720.pdf
", "abstract": "No, in a rigorous sense specified below.", "date": "2017-06-06", "date_type": "published", "id_number": "CaltechAUTHORS:20170606-064632154", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170606-064632154", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-2644" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1701.00720", "primary_object": { "basename": "1701.00720.pdf", "url": "https://authors.library.caltech.edu/records/c71hk-tp411/files/1701.00720.pdf" }, "pub_year": "2017", "author_list": "Huang, Yichen" }, { "id": "https://authors.library.caltech.edu/records/xkdkq-8sb12", "eprint_id": 70804, "eprint_status": "archive", "datestamp": "2023-08-20 06:24:01", "lastmod": "2023-10-20 23:31:41", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Temme-K", "name": { "family": "Temme", "given": "Kristan" } }, { "id": "Kastoryano-M", "name": { "family": "Kastoryano", "given": "Michael" } } ] }, "title": "How fast do stabilizer Hamiltonians thermalize?", "ispublished": "unpub", "full_text_status": "public", "note": "Dated: May 29, 2015. \n\nWe thank F. Pastawski and F. Brandao for helpful discussions. This work was supported by the Carlsbergfond, the Villum foundation, the Humboldt foundation, the Institute for Quantum Information and Matter, a NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation (Grants No. PHY-0803371 and PHY-1125565).\n\nSubmitted - 1505.07811v1.pdf
", "abstract": "We present rigorous bounds on the thermalization time of the family of quantum mechanical spin systems\nknown as stabilizer Hamiltonians. The thermalizing dynamics are modeled by a Davies master equation that\narises from a weak local coupling of the system to a large thermal bath. Two temperature regimes are considered.\nFirst we clarify how in the low temperature regime, the thermalization time is governed by a generalization\nof the energy barrier between orthogonal ground states. When no energy barrier is present the Hamiltonian\nthermalizes in a time that is at most quadratic in the system size. Secondly, we show that above a universal\ncritical temperature, every stabilizer Hamiltonian relaxes to its unique thermal state in a time which scales at\nmost linearly in the size of the system. We provide an explicit lower bound on the critical temperature. Finally,\nwe discuss the implications of these result for the problem of self-correcting quantum memories with stabilizer\nHamiltonians.", "date": "2016-10-04", "date_type": "published", "id_number": "CaltechAUTHORS:20161004-093445721", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161004-093445721", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Carlsbergfond" }, { "agency": "Villum Foundation" }, { "agency": "Alexander von Humboldt Foundation" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF Physics Frontiers Center" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "NSF", "grant_number": "PHY-0803371" }, { "agency": "NSF", "grant_number": "PHY-1125565" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1505.07811", "primary_object": { "basename": "1505.07811v1.pdf", "url": "https://authors.library.caltech.edu/records/xkdkq-8sb12/files/1505.07811v1.pdf" }, "pub_year": "2016", "author_list": "Temme, Kristan and Kastoryano, Michael" }, { "id": "https://authors.library.caltech.edu/records/npddy-55a18", "eprint_id": 68586, "eprint_status": "archive", "datestamp": "2023-08-20 08:11:35", "lastmod": "2023-10-19 22:20:04", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brown-E", "name": { "family": "Brown", "given": "Emory" } }, { "id": "Bao-Ning", "name": { "family": "Bao", "given": "Ning" }, "orcid": "0000-0002-3296-1039" }, { "id": "Nezami-S", "name": { "family": "Nezami", "given": "Sepehr" } } ] }, "title": "Non-linear Holographic Entanglement Entropy Inequalities for Single Boundary 2D CFT", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Sepehr Nezami, Hirosi Ooguri, John Preskill, Bogdan Stoica, James Sully, and Michael Walter. The work of Ning Bao is supported by a Dubridge Postdoctoral Fellowship.\n\nSubmitted - 1508.05441v2.pdf
", "abstract": "Significant work has gone into determining the minimal set of entropy inequalities that determine the holographic entropy cone. Holographic systems with three or more parties have been shown to obey additional inequalities that generic quantum systems do not. We consider a two dimensional conformal field theory that is a single boundary of a holographic system and find four additional non-linear inequalities which are derived from strong subadditivity and the formula for the entanglement entropy of a region on the conformal field theory. We also present an equality obtained by application of a hyperbolic extension of Ptolemy's theorem to a two dimensional conformal field theory.", "date": "2016-06-27", "date_type": "published", "publisher": "N/A", "id_number": "CaltechAUTHORS:20160622-113714676", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160622-113714676", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-2644" }, { "agency": "DuBridge Postdoctoral Fellowship" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.1508.05441", "primary_object": { "basename": "1508.05441v2.pdf", "url": "https://authors.library.caltech.edu/records/npddy-55a18/files/1508.05441v2.pdf" }, "pub_year": "2016", "author_list": "Brown, Emory; Bao, Ning; et el." }, { "id": "https://authors.library.caltech.edu/records/s45t1-jbk91", "eprint_id": 68584, "eprint_status": "archive", "datestamp": "2023-08-20 11:00:21", "lastmod": "2023-10-19 22:19:57", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bao-Ning", "name": { "family": "Bao", "given": "Ning" }, "orcid": "0000-0002-3296-1039" }, { "id": "He-Temple", "name": { "family": "He", "given": "Temple" } } ] }, "title": "Limitations on Dimensional Regularization in Renyi Entropy", "ispublished": "unpub", "full_text_status": "public", "note": "We would like to thank L. Bianchi, A. Lewkowycz, and S. Solodukhin for useful conversations. We would especially like to thank M. Headrick for reading the preprint and providing useful comments and feedback. N.B. is supported by the DuBridge Postdoctoral Fellowship, and also by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NFS Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028).\n\nSubmitted - 1603.08531v1.pdf
", "abstract": "Dimensional regularization is a common method used to regulate the UV divergence of field theoretic quantities. When it is used in the context of Renyi entropy, however, it is important to consider whether such a procedure eliminates the statistical interpretation thereof as a measure of entanglement of states living on a Hilbert space. We therefore examine the dimensionally regularized Renyi entropy of a 4d unitary CFT and show that it admits no underlying Hilbert space in the state-counting sense. This gives a concrete proof that dimensionally regularized Renyi entropy cannot always be obtained as a limit of the Renyi entropy of some finite-dimensional quantum system.", "date": "2016-06-27", "date_type": "published", "publisher": "N/A", "id_number": "CaltechAUTHORS:20160622-112748138", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160622-112748138", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "DuBridge Postdoctoral Fellowship" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.1603.08531", "primary_object": { "basename": "1603.08531v1.pdf", "url": "https://authors.library.caltech.edu/records/s45t1-jbk91/files/1603.08531v1.pdf" }, "pub_year": "2016", "author_list": "Bao, Ning and He, Temple" }, { "id": "https://authors.library.caltech.edu/records/5xv5m-h1253", "eprint_id": 68585, "eprint_status": "archive", "datestamp": "2023-08-20 10:01:35", "lastmod": "2023-10-19 22:20:00", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bao-Ning", "name": { "family": "Bao", "given": "Ning" }, "orcid": "0000-0002-3296-1039" }, { "id": "Kim-Isaac-H", "name": { "family": "Kim", "given": "Isaac H." } } ] }, "title": "Precursor problem and holographic mutual information", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted on 28 Jan 2016.\n\nWe would like to thank Xi Dong for useful discussions. We thank the Perimeter\nInstitute for hospitality during parts of this project. Ning Bao is supported by the DOE\nGrant DE-SC0011632 and funding provided by the Institute for Quantum Information\nand Matter, an NSF Physics Frontiers Center (NSF Grant PHY-1125565) with support\nof the Gordon and Betty Moore Foundation (GBMF-2644). He is also supported by\nthe Walter Burke Institute of Theoretical Physics. Isaac Kim's research at Perimeter\nInstitute is supported in part by the Government of Canada through NSERC and by\nthe Province of Ontario through MRI.\n\nSubmitted - 1601.07616v3.pdf
", "abstract": "The recent proposal of Almheiri et al.[http://arxiv.org/abs/1411.7041], together with the Ryu-Takayanagi formula, implies the entanglement wedge hypothesis for certain choices of boundary subregions. This fact is derived in the pure AdS space. A similar conclusion holds in the presence of quantum corrections, but in a more restricted domain of applicability. We also comment on this [http://arxiv.org/abs/1601.05416] and some similarities and differences with this work.", "date": "2016-06-23", "date_type": "published", "publisher": "Journal of High Energy Physics", "id_number": "CaltechAUTHORS:20160622-113158636", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160622-113158636", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0011632" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-2644" }, { "agency": "Walter Burke Institute for Theoretical Physics, Caltech" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Ontario Ministry of Research and Innovation" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.1601.07616", "primary_object": { "basename": "1601.07616v3.pdf", "url": "https://authors.library.caltech.edu/records/5xv5m-h1253/files/1601.07616v3.pdf" }, "pub_year": "2016", "author_list": "Bao, Ning and Kim, Isaac H." }, { "id": "https://authors.library.caltech.edu/records/478bj-z4482", "eprint_id": 67560, "eprint_status": "archive", "datestamp": "2023-08-20 09:02:58", "lastmod": "2023-10-18 21:17:32", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jeffery-S", "name": { "family": "Jeffery", "given": "Stacey" } }, { "id": "Kimmel-S", "name": { "family": "Kimmel", "given": "Shelby" } } ] }, "title": "NAND-Trees, Average Choice Complexity, and Effective Resistance", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted on 6 Nov 2015. \n\nThe authors would like to thank Ashley Montanaro for helpful discussions. \n\nS.J. gratefully acknowledges funding provided by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NFS Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028). S.K. acknowledges funds provided by the Department of Defense.\n\nSubmitted - 1511.02235v1.pdf
", "abstract": "We show that the quantum query complexity of evaluating nand-tree instances with average choice complexity at most W is O(W), where average choice complexity is a measure of the difficulty of winning the associated two-player game. This generalizes a superpolynomial speedup over classical query complexity due to Zhan et al. We further show that the player with a winning strategy for the two-player game associated with the nand-tree can win the game with an expected \u00d5(N^(1/4) \u221aC(x)) quantum queries against a random opponent, where C(x) is the average choice complexity of the instance. This gives an improvement over the query\ncomplexity of the naive strategy, which costs \u00d5(\u221aN) queries.\nThe results rely on a connection between nand-tree evaluation and st-connectivity problems on certain graphs, and span programs for st-connectivity problems. Our results follow from relating average choice complexity to the effective resistance of these graphs, which itself\ncorresponds to the span program witness size.", "date": "2016-06-02", "date_type": "published", "id_number": "CaltechAUTHORS:20160602-065519464", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160602-065519464", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF Physics Frontiers Center", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" }, { "agency": "Department of Defense" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1511.02235", "primary_object": { "basename": "1511.02235v1.pdf", "url": "https://authors.library.caltech.edu/records/478bj-z4482/files/1511.02235v1.pdf" }, "pub_year": "2016", "author_list": "Jeffery, Stacey and Kimmel, Shelby" }, { "id": "https://authors.library.caltech.edu/records/cmamh-kwj05", "eprint_id": 67161, "eprint_status": "archive", "datestamp": "2023-08-20 11:39:54", "lastmod": "2023-10-18 20:36:35", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chung-Kai-Min", "name": { "family": "Chung", "given": "Kai-Min" } }, { "id": "Cohen-Gil", "name": { "family": "Cohen", "given": "Gil" } }, { "id": "Vidick-T", "name": { "family": "Vidick", "given": "Thomas" }, "orcid": "0000-0002-6405-365X" }, { "id": "Wu-Xiaodi", "name": { "family": "Wu", "given": "Xiaodi" } } ] }, "title": "Quantum-Proof Extractors: Optimal up to Constant Factors", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Yanlin Chen, Yi-Hsiu Chen, Anindya De, Andrew Drucker, Robert K\u00a8onig, Ashwin Nayak,\nSalil Vadhan, and Nengkun Yu for helpful discussions. Part of the research was conducted when KC\nand XW were visiting the Institute for Quantum Computing, University of Waterloo and we thank IQC\nfor its hospitality. Part of the research was conducted while XW was affiliated with the Simons Institute\nfor the Theory of Computing, University of California, Berkeley and with the Center for Theoretical\nPhysics, Massachusetts Institute of Technology. TV was partially supported by NSF CAREER Grant\nCCF-1553477, an AFOSR YIP award, and the IQIM, an NSF Physics Frontiers Center (NFS Grant\nPHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028).\n\nSubmitted - 1605.04194v1.pdf
", "abstract": "We give the first construction of a family of quantum-proof extractors that has optimal seed\nlength dependence O(log(n/\u01eb)) on the input length n and error \u01eb. Our extractors support any\nmin-entropy k = \u03a9(log n + log1+\u03b1\n(1/\u01eb)) and extract m = (1 \u2212 \u03b1)k bits that are \u01eb-close to uniform,\nfor any desired constant \u03b1 > 0. Previous constructions had a quadratically worse seed length or\nwere restricted to very large input min-entropy or very few output bits.\nOur result is based on a generic reduction showing that any strong classical condenser is automatically\nquantum-proof, with comparable parameters. The existence of such a reduction for\nextractors is a long-standing open question; here we give an affirmative answer for condensers.\nOnce this reduction is established, to obtain our quantum-proof extractors one only needs to consider\nhigh entropy sources. We construct quantum-proof extractors with the desired parameters\nfor such sources by extending a classical approach to extractor construction, based on the use of\nblock-sources and sampling, to the quantum setting.\nOur extractors can be used to obtain improved protocols for device-independent randomness\nexpansion and for privacy amplification.", "date": "2016-05-13", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20160517-182619760", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160517-182619760", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CCF-1553477" }, { "agency": "Air Force Office of Scientific Research (AFOSR)" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "12500028" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1605.04194", "primary_object": { "basename": "1605.04194v1.pdf", "url": "https://authors.library.caltech.edu/records/cmamh-kwj05/files/1605.04194v1.pdf" }, "pub_year": "2016", "author_list": "Chung, Kai-Min; Cohen, Gil; et el." }, { "id": "https://authors.library.caltech.edu/records/386jx-np407", "eprint_id": 66493, "eprint_status": "archive", "datestamp": "2023-08-20 11:21:55", "lastmod": "2023-10-18 18:08:53", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Preskill-J", "name": { "family": "Preskill", "given": "John" } } ] }, "title": "Quantum Shannon Theory", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted - 1604.07450v1.pdf
Updated - chap10_15.pdf
", "abstract": "This is the 10th and final chapter of my book on Quantum Information, based\non the course I have been teaching at Caltech since 1997. An early version of\nthis chapter (originally Chapter 5) has been available on the course website\nsince 1998, but this version is substantially revised and expanded. The level\nof detail is uneven, as I've aimed to provide a gentle introduction, but I've\nalso tried to avoid statements that are incorrect or obscure. Generally\nspeaking, I chose to include topics that are both useful to know and relatively\neasy to explain; I had to leave out a lot of good stuff, but on the other hand\nthe chapter is already quite long. This is a working draft of Chapter 10, which\nI will continue to update. See the URL on the title page for further updates\nand drafts of other chapters, and please send me an email if you notice errors.\nEventually, the complete book will be published by Cambridge University Press.", "date": "2016-04-27", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20160426-213243084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160426-213243084", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1604.07450", "primary_object": { "basename": "1604.07450v1.pdf", "url": "https://authors.library.caltech.edu/records/386jx-np407/files/1604.07450v1.pdf" }, "related_objects": [ { "basename": "chap10_15.pdf", "url": "https://authors.library.caltech.edu/records/386jx-np407/files/chap10_15.pdf" } ], "pub_year": "2016", "author_list": "Preskill, John" }, { "id": "https://authors.library.caltech.edu/records/6qts1-9xt55", "eprint_id": 65884, "eprint_status": "archive", "datestamp": "2023-08-20 07:41:40", "lastmod": "2023-10-18 16:53:36", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yi-Xu", "name": { "family": "Yi", "given": "Xu" }, "orcid": "0000-0002-2485-1104" }, { "id": "Yang-Qi-Fan", "name": { "family": "Yang", "given": "Qi-Fan" }, "orcid": "0000-0002-7036-1712" }, { "id": "Yang-Ki-Youl", "name": { "family": "Yang", "given": "Ki Youl" }, "orcid": "0000-0002-0587-3201" }, { "id": "Suh-Myoung-Gyun", "name": { "family": "Suh", "given": "Myoung-Gyun" }, "orcid": "0000-0002-9527-0585" }, { "id": "Vahala-K-J", "name": { "family": "Vahala", "given": "Kerry J." }, "orcid": "0000-0003-1783-1380" } ] }, "title": "Generation of high-stability solitons at microwave rates on a silicon chip", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted on 1 Aug 2015. \n\nThe authors thank Tobias Kippenberg, Victor Brasch at EPFL and Michael Gorodetsky at Moscow State University for helpful discussions and comments on this manuscript. The authors gratefully acknowledge the Defense Advanced Research Projects Agency under the QuASAR program and the PULSE program, the Kavli Nanoscience Institute and the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation.\n\nSubmitted - 1508.00170v1.pdf
", "abstract": "Because they coherently link radio/microwave-rate electrical signals with optical-rate signals derived from lasers and atomic transitions, frequency combs are having a remarkably broad impact on science and technology. Integrating these systems on a photonic chip would revolutionize instrumentation, time keeping, spectroscopy, navigation and potentially create new mass-market applications. A key element of such a system-on-a-chip will be a mode-locked comb that can be self-referenced. The recent demonstration of soliton pulses from a microresonator has placed this goal within reach. However, to provide the requisite link between microwave and optical rate signals soliton generation must occur within the bandwidth of electronic devices. So far this is possible in crystalline devices, but not chip-based devices. Here, a monolithic comb that generates electronic-rate soliton pulses is demonstrated.", "date": "2016-04-04", "date_type": "published", "id_number": "CaltechAUTHORS:20160404-091735690", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160404-091735690", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Advanced Research Projects Agency (DARPA)" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF Physics Frontiers Center" }, { "agency": "Gordon and Betty Moore Foundation" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1508.00170", "primary_object": { "basename": "1508.00170v1.pdf", "url": "https://authors.library.caltech.edu/records/6qts1-9xt55/files/1508.00170v1.pdf" }, "pub_year": "2016", "author_list": "Yi, Xu; Yang, Qi-Fan; et el." }, { "id": "https://authors.library.caltech.edu/records/mkbh9-tmy79", "eprint_id": 65495, "eprint_status": "archive", "datestamp": "2023-08-20 09:27:08", "lastmod": "2023-10-18 16:04:29", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Natarajan-A", "name": { "family": "Natarajan", "given": "Anand" }, "orcid": "0000-0003-3648-3844" }, { "id": "Vidick-T", "name": { "family": "Vidick", "given": "Thomas" }, "orcid": "0000-0002-6405-365X" } ] }, "title": "Constant-Soundness Interactive Proofs for Local Hamiltonians", "ispublished": "unpub", "full_text_status": "public", "note": "AN was supported by the ARO grant Contract Number W911NF-12-0486. Parts of this work was completed while the second author was visiting the Institute for Quantum Information and Matter (IQIM) at Caltech, and both authors acknowledge funding provided by the IQIM, an NSF Physics Frontiers Center (NFS Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028).\n\nSubmitted - 1512.02090.pdf
", "abstract": "We give a quantum multiprover interactive proof system for the local Hamiltonian problem in which there is a constant number of provers, questions are classical of length polynomial in the number of qubits, and answers are of constant length. The main novelty of our protocol is that the gap between completeness and soundness is directly proportional to the promise gap on the (normalized) ground state energy of the Hamiltonian. This result can be interpreted as a concrete step towards a quantum PCP theorem giving entangled-prover interactive proof systems for QMA-complete problems. \n\nThe key ingredient is a quantum version of the classical linearity test of Blum, Luby, and Rubinfeld, where the function f : {0,1}^n \u2192 {0,1} is replaced by a pair of functions X,Z : {0,1}^n \u2192 Obs_d(C), the set of d-dimensional Hermitian matrices that square to identity. The test enforces that (i) each function is exactly linear, X(a)X(b) = X(a+b) and Z(a)Z(b) = Z(a+b), and (ii) the two functions are approximately complementary, X(a)Z(b) \u2248 (\u22121)^(a\u22c5b)Z(b)X(a).", "date": "2016-03-18", "date_type": "published", "id_number": "CaltechAUTHORS:20160318-160143988", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160318-160143988", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-12-0486" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1512.02090", "primary_object": { "basename": "1512.02090.pdf", "url": "https://authors.library.caltech.edu/records/mkbh9-tmy79/files/1512.02090.pdf" }, "pub_year": "2016", "author_list": "Natarajan, Anand and Vidick, Thomas" }, { "id": "https://authors.library.caltech.edu/records/2vw8q-74k92", "eprint_id": 64142, "eprint_status": "archive", "datestamp": "2023-08-20 09:02:26", "lastmod": "2023-10-17 19:32:44", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Yichen", "name": { "family": "Huang", "given": "Yichen" } } ] }, "title": "A simple efficient algorithm in frustration-free one-dimensional gapped systems", "ispublished": "unpub", "full_text_status": "public", "note": "Dated: November 5, 2015. \n\nWe acknowledge funding provided by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-12500028). In May 2015, Zeph Landau announced his joint work with Itai Arad, Umesh Vazirani, and Thomas Vidick on related problems in a talk [6] at the Simons Institute for the Theory of Computing. From the talk, the connection between their approach and the one in the present paper was not clear to me. Thanks to the correspondence with ZL in mid-October 2015, I realized that my approach has some overlap with theirs. Although the present work is independent, IA, ZL, UV, & TV deserve the credit of the overlapping part because they had the ideas since May 2015. They will post their results soon.\n\nSubmitted - 1510.01303v3.pdf
", "abstract": "We propose an efficient algorithm for the ground state of frustration-free one-dimensional gapped\nHamiltonians. This algorithm is much simpler than the original one by Landau et al., and thus may\nbe easily accessible to a general audience in the community. We present all the details in two pages.", "date": "2016-02-03", "date_type": "published", "id_number": "CaltechAUTHORS:20160201-153526027", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160201-153526027", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF Physics Frontiers Center", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-12500028" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1510.01303", "primary_object": { "basename": "1510.01303v3.pdf", "url": "https://authors.library.caltech.edu/records/2vw8q-74k92/files/1510.01303v3.pdf" }, "pub_year": "2016", "author_list": "Huang, Yichen" }, { "id": "https://authors.library.caltech.edu/records/ke0p0-pq640", "eprint_id": 63488, "eprint_status": "archive", "datestamp": "2023-08-20 05:47:46", "lastmod": "2023-10-25 23:51:36", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Huan", "name": { "family": "Yang", "given": "Huan" } }, { "id": "Price-L-R", "name": { "family": "Price", "given": "Larry R." } }, { "id": "Smith-N-D", "name": { "family": "Smith", "given": "Nicholas D." } }, { "id": "Adhikari-R-X", "name": { "family": "Adhikari", "given": "Rana X." }, "orcid": "0000-0002-5731-5076" }, { "id": "Miao-Haixing", "name": { "family": "Miao", "given": "Haixing" }, "orcid": "0000-0003-2879-5821" }, { "id": "Chen-Yanbei", "name": { "family": "Chen", "given": "Yanbei" }, "orcid": "0000-0002-9730-9463" } ] }, "title": "Towards the Laboratory Search for Space-Time Dissipation", "ispublished": "unpub", "full_text_status": "public", "keywords": "General Relativity, Quantum Cosmology", "note": "We thank Rai Weiss, Eric K. Gustafson, Jan Harms,\nNico Yunes, Yuri Levin, Poghos Kazarian and John\nPreskill for illuminating discussions. We acknowledge\nfunding provided by the Institute for Quantum Information\nand Matter, an NSF Physics Frontiers Center with\nsupport of the Gordon and Betty Moore Foundation.\nHY, HM, and YC are supported by NSF Grant PHY-0601459, PHY-0653653, CAREER Grant PHY-0956189,\nand the David and Barbara Groce Startup Fund at the\nCalifornia Institute of Technology. RXA, NDSL and LP\nare supported by the National Science Foundation under\ngrant PHY-0555406. Research at Perimeter Institute is\nsupported through Industry Canada and by the Province\nof Ontario through the Ministry of Research & Innovation.\n\nSubmitted - 1504.02545v2.pdf
", "abstract": "It has been speculated that gravity could be an emergent phenomenon, with classical general relativity as an effective, macroscopic theory, valid only for classical systems at large temporal and spatial scales. As in classical continuum dynamics, the existence of underlying microscopic degrees of freedom may lead to macroscopic dissipative behaviors. With the hope that such dissipative behaviors of gravity could be revealed by carefully designed experiments in the laboratory, we consider a phenomenological model that adds dissipations to the gravitational field, much similar to frictions in solids and fluids. Constraints to such dissipative behavior can already be imposed by astrophysical observations and existing experiments, but mostly in lower frequencies. We propose a series of experiments working in higher frequency regimes, which may potentially put more stringent bounds on these models.", "date": "2016-01-11", "date_type": "published", "publisher": "Towards the Laboratory Search for Space-Time Dissipation", "id_number": "CaltechAUTHORS:20160108-094643919", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160108-094643919", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-1125565" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF-2644" }, { "agency": "NSF", "grant_number": "PHY- 0601459" }, { "agency": "NSF", "grant_number": "PHY-0653653" }, { "agency": "NSF", "grant_number": "PHY-0956189" }, { "agency": "NSF", "grant_number": "PHY-0555406" }, { "agency": "David and Barbara Groce Startup Fund, Caltech" }, { "agency": "Industry Canada" }, { "agency": "Ontario Ministry of Research and Innovation" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1504.02545", "primary_object": { "basename": "1504.02545v2.pdf", "url": "https://authors.library.caltech.edu/records/ke0p0-pq640/files/1504.02545v2.pdf" }, "pub_year": "2016", "author_list": "Yang, Huan; Price, Larry R.; et el." }, { "id": "https://authors.library.caltech.edu/records/msq05-8cs48", "eprint_id": 59829, "eprint_status": "archive", "datestamp": "2023-08-20 06:49:18", "lastmod": "2023-10-23 22:45:27", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Krause-A-G", "name": { "family": "Krause", "given": "Alex G." } }, { "id": "Blasius-T-D", "name": { "family": "Blasius", "given": "Tim D." } }, { "id": "Painter-O", "name": { "family": "Painter", "given": "Oskar" }, "orcid": "0000-0002-1581-9209" } ] }, "title": "Optical read out and feedback cooling of a nanostring optomechanical cavity", "ispublished": "unpub", "full_text_status": "public", "note": "The authors would like to thank Dal Wilson and Kartik Srinivasan for helpful discussions. This work was supported by the DARPA QuASaR program through a grant from the Army Research Office, the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation, and the Kavli Nanoscience Institute at Caltech. TDB gratefully acknowledges support from the National Science Foundation Graduate Research Fellowship Program (grant no. 0703267).\n\nSubmitted - 1506.01249v1.pdf
", "abstract": "Optical measurement of the motion of a 940 kHz mechanical resonance of a silicon nitride nanostring resonator is demonstrated with a read out noise imprecision reaching 37 dB below that of the resonator's zero-point fluctuations. Via intensity modulation of the optical probe laser, radiation pressure feedback is used to cool and damp the mechanical mode from an initial room temperature occupancy of n_b=6.5\u00d710^6 (T_b=295K) down to a phonon occupation of (n)=66\u00b110, representing a mode temperature of T_m\u22483mK. The five decades of cooling is enabled by the system's large single-photon cooperativity (C_1=4) and high quantum efficiency of optical motion detection (\u03b7_t=0.27).", "date": "2015-08-24", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20150824-081716175", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150824-081716175", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-0703267" }, { "agency": "Army Research Office (ARO)" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.48550/arXiv.1506.01249", "primary_object": { "basename": "1506.01249v1.pdf", "url": "https://authors.library.caltech.edu/records/msq05-8cs48/files/1506.01249v1.pdf" }, "pub_year": "2015", "author_list": "Krause, Alex G.; Blasius, Tim D.; et el." }, { "id": "https://authors.library.caltech.edu/records/yydxn-hbh88", "eprint_id": 59828, "eprint_status": "archive", "datestamp": "2023-08-20 07:49:12", "lastmod": "2023-10-23 22:45:24", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fang-Kejie", "name": { "family": "Fang", "given": "Kejie" } }, { "id": "Matheny-M-H", "name": { "family": "Matheny", "given": "Matthew H." }, "orcid": "0000-0002-3488-1083" }, { "id": "Luan-Xingsheng", "name": { "family": "Luan", "given": "Xingsheng" } }, { "id": "Painter-O", "name": { "family": "Painter", "given": "Oskar" }, "orcid": "0000-0002-1581-9209" } ] }, "title": "Phonon routing in integrated optomechanical cavity-waveguide systems", "ispublished": "unpub", "full_text_status": "public", "note": "The authors would like to thank Justin Cohen and Sean Meenehan for help with device fabrication and design. This work was supported by the AFOSR Hybrid Nanophotonics MURI, DARPA ORCHID and MESO programs, the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center with support of the Gordon and Betty Moore Foundation, and the Kavli Nanoscience Institute at Caltech.\n\nSubmitted - 1508.05138v1.pdf
", "abstract": "The mechanical properties of light have found widespread use in the\nmanipulation of gas-phase atoms and ions, helping create new states of matter\nand realize complex quantum interactions. The field of cavity-optomechanics\nstrives to scale this interaction to much larger, even human-sized mechanical\nobjects. Going beyond the canonical Fabry-Perot cavity with a movable mirror,\nhere we explore a new paradigm in which multiple cavity-optomechanical elements\nare wired together to form optomechanical circuits. Using a pair of\noptomechanical cavities coupled together via a phonon waveguide we demonstrate\na tunable delay and filter for microwave-over-optical signal processing. In\naddition, we realize a tight-binding form of mechanical coupling between\ndistant optomechanical cavities, leading to direct phonon exchange without\ndissipation in the waveguide. These measurements indicate the feasibility of\nphonon-routing based information processing in optomechanical crystal\ncircuitry, and further, to the possibility of realizing topological phases of\nphotons and phonons in optomechanical cavity lattices.", "date": "2015-08-24", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20150824-080921056", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150824-080921056", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)" }, { "agency": "NSF" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.48550/arXiv.1508.05138", "primary_object": { "basename": "1508.05138v1.pdf", "url": "https://authors.library.caltech.edu/records/yydxn-hbh88/files/1508.05138v1.pdf" }, "pub_year": "2015", "author_list": "Fang, Kejie; Matheny, Matthew H.; et el." }, { "id": "https://authors.library.caltech.edu/records/sns6a-g4p70", "eprint_id": 47509, "eprint_status": "archive", "datestamp": "2023-08-20 01:49:30", "lastmod": "2023-10-26 20:39:47", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pitanti-A", "name": { "family": "Pitanti", "given": "Alessandro" } }, { "id": "Fink-J-M", "name": { "family": "Fink", "given": "Johannes M." }, "orcid": "0000-0001-8112-028X" }, { "id": "Safavi-Naeini-A-H", "name": { "family": "Safavi-Naeini", "given": "Amir H." }, "orcid": "0000-0001-6176-1274" }, { "id": "Lei-Chan-U", "name": { "family": "Lei", "given": "Chan U." } }, { "id": "Hill-J-T", "name": { "family": "Hill", "given": "Jeff T." } }, { "id": "Tredicucci-A", "name": { "family": "Tredicucci", "given": "Alessandro" } }, { "id": "Painter-O", "name": { "family": "Painter", "given": "Oskar" }, "orcid": "0000-0002-1581-9209" } ] }, "title": "Linear and nonlinear capacitive coupling of electro-opto-mechanical photonic crystal cavities", "ispublished": "unpub", "full_text_status": "public", "note": "This work was supported by the DARPA MESO program,\nthe AFOSR Hybrid Nanophotonics MURI, the Institute for\nQuantum Information and Matter, an NSF Physics Frontiers\nCenter with support of the Gordon and Betty Moore Foundation,\nand the Kavli Nanoscience Institute at Caltech. AP gratefully\nacknowledge funding from EU through Marie Curie Actions,\nproject NEMO (GA 298861). AT acknowledges partial\nfinancial support from the ERC through the advanced grant\nSoulMan.\n\nSubmitted - 1407.2982.pdf
", "abstract": "We fabricate and characterize a microscale silicon electro-opto-mechanical system whose mechanical motion is coupled capacitively to an electrical circuit and optically via radiation pressure to a photonic crystal cavity. To achieve large electromechanical interaction strength, we implement an inverse shadow mask fabrication scheme which obtains capacitor gaps as small as 30 nm while maintaining a silicon surface quality necessary for minimizing optical loss. Using the sensitive optical read-out of the photonic crystal cavity, we characterize the linear and nonlinear capacitive coupling to the fundamental 63 MHz in-plane flexural motion of the structure, showing that the large electromechanical coupling in such devices may be suitable for realizing efficient microwave-to-optical signal conversion.", "date": "2014-07-28", "date_type": "published", "id_number": "CaltechAUTHORS:20140728-081038978", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140728-081038978", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Advanced Research Projects Agency (DARPA)" }, { "agency": "Air Force Office of Scientific Research (AFOSR)" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "NSF Physics Frontiers Center" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Marie Curie Fellowship", "grant_number": "GA 298861" }, { "agency": "European Research Council (ERC)", "grant_number": "SoulMan" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.48550/arXiv.1407.2982", "primary_object": { "basename": "1407.2982.pdf", "url": "https://authors.library.caltech.edu/records/sns6a-g4p70/files/1407.2982.pdf" }, "pub_year": "2014", "author_list": "Pitanti, Alessandro; Fink, Johannes M.; et el." }, { "id": "https://authors.library.caltech.edu/records/ht0vt-5qb26", "eprint_id": 47247, "eprint_status": "archive", "datestamp": "2023-08-19 23:34:37", "lastmod": "2023-10-26 20:26:19", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lindner-N-H", "name": { "family": "Lindner", "given": "Netanel H." }, "orcid": "0000-0003-1879-3902" }, { "id": "Refael-G", "name": { "family": "Refael", "given": "Gil" } }, { "id": "von-Oppen-F", "name": { "family": "von Oppen", "given": "Felix" } } ] }, "title": "Enhancement of surface photocurrents in topological insulators using magnetic superlattices", "ispublished": "unpub", "full_text_status": "public", "note": "Imported from arXiv.\n\nSubmitted - 1403.0010v1.pdf
", "abstract": "The gapless surface states of topological insulators (TI) can potentially be used to detect and harvest low-frequency infrared light. Nonetheless, it was shown that significant surface photocurrents due to light with frequency below\nthe bulk gap are rather hard to produce. Here we demonstrate that a periodic\nmagnetic pattern added to the surface dramatically enhances surface photocurrents in TI's . The ability to produce substantial photocurrents on TI surfaces from mid-range and far-infrared light could be used in photovoltaic applications, as well as for detection of micrometer wavelength radiation.", "date": "2014-07-16", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20140715-162801579", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140715-162801579", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Packard Foundation" }, { "agency": "NSF, Physics Frontier Center, Institute for Quantum Information and Matter (IQIM)", "grant_number": "1125565" }, { "agency": "Defense Advanced Research Projects Agency, Functional Engineered Nano Architectonics (FENA)" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Binational Science Foundation (USA-Israel)" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1403.0010v1", "primary_object": { "basename": "1403.0010v1.pdf", "url": "https://authors.library.caltech.edu/records/ht0vt-5qb26/files/1403.0010v1.pdf" }, "pub_year": "2014", "author_list": "Lindner, Netanel H.; Refael, Gil; et el." }, { "id": "https://authors.library.caltech.edu/records/pt01q-wdy02", "eprint_id": 45969, "eprint_status": "archive", "datestamp": "2023-08-20 00:28:50", "lastmod": "2023-10-26 18:34:56", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jordan-S-P", "name": { "family": "Jordan", "given": "Stephen P." } }, { "id": "Lee-S-M", "name": { "family": "Lee", "given": "Keith S. M." } }, { "id": "Preskill-J", "name": { "family": "Preskill", "given": "John" } } ] }, "title": "Quantum Algorithms for Fermionic Quantum Field Theories", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted on April 28 2014.\n\nWe thank William George for help with numerical calculation\ns. This work\nwas supported by NSF grant PHY-0803371, DOE grant DE-FG03-9\n2-ER40701, and NSA/ARO\ngrant W911NF-09-1-0442. IQC and Perimeter Institute are \nsupported in part by the Government of Canada through Industry Canada and by the Province of Ontario through the Ministry of\nResearch and Innovation. The Institute for Quantum Informa\ntion and Matter (IQIM) is an NSF\nphysics Frontiers Center with support from the Gordon and Betty Moore Foundation. S.J. and K.L. are grateful for the hospitality of the IQIM (formerly IQI), Caltech, during parts of this work. Portions of this work are a contribution of NIST, an agency of the US Government, and are not\nsubject to US copyright.\n\nSubmitted - 1404.7115v1.pdf
", "abstract": "Extending previous work on scalar field theories, we develop a quantum\nalgorithm to compute relativistic scattering amplitudes in fermionic field\ntheories, exemplified by the massive Gross-Neveu model, a theory in two\nspacetime dimensions with quartic interactions. The algorithm introduces new\ntechniques to meet the additional challenges posed by the characteristics of\nfermionic fields, and its run time is polynomial in the desired precision and\nthe energy. Thus, it constitutes further progress towards an efficient quantum\nalgorithm for simulating the Standard Model of particle physics.", "date": "2014-05-29", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20140529-115454760", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140529-115454760", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-0803371" }, { "agency": "DOE", "grant_number": "DE-FG03-9 2-ER40701" }, { "agency": "National Security Agency/Army Research Office", "grant_number": "W911NF-09-1-0442" }, { "agency": "Government of Canada" }, { "agency": "Province of Ontario" }, { "agency": "Gordon and Betty Moore Foundation" } ] }, "other_numbering_system": { "items": [ { "id": "2014-136", "name": "CALT-TH" } ] }, "local_group": { "items": [ { "id": "Caltech-Theory" }, { "id": "IQIM" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.48550/arXiv.1404.7115", "primary_object": { "basename": "1404.7115v1.pdf", "url": "https://authors.library.caltech.edu/records/pt01q-wdy02/files/1404.7115v1.pdf" }, "pub_year": "2014", "author_list": "Jordan, Stephen P.; Lee, Keith S. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/aq0vm-7x550", "eprint_id": 44606, "eprint_status": "archive", "datestamp": "2023-08-19 23:58:23", "lastmod": "2023-10-26 14:48:59", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Meenehan-S-M", "name": { "family": "Meenehan", "given": "Se\u00e1n M." } }, { "id": "Cohen-J-D", "name": { "family": "Cohen", "given": "Justin D." } }, { "id": "Gr\u00f6blacher-S", "name": { "family": "Gr\u00f6blacher", "given": "Simon" } }, { "id": "Hill-J-T", "name": { "family": "Hill", "given": "Jeff T." } }, { "id": "Safavi-Naeini-A-H", "name": { "family": "Safavi-Naeini", "given": "Amir H." }, "orcid": "0000-0001-6176-1274" }, { "id": "Aspelmeyer-M", "name": { "family": "Aspelmeyer", "given": "Markus" } }, { "id": "Painter-O", "name": { "family": "Painter", "given": "Oskar" }, "orcid": "0000-0002-1581-9209" } ] }, "title": "Thermalization properties at mK temperatures of a nanoscale optomechanical resonator with acoustic-bandgap shield", "ispublished": "unpub", "full_text_status": "public", "note": "The authors would like to thank Michael Roukes, Ron\nLifshitz, and Michael Cross for helpful discussions regarding\nthe proposed thermal model, as well as Jasper Chan,\nWitlef Wiezcorek, and Jason Hoelscher-Obermaier for\nsupport in the early stages of the experiment. This work\nwas supported by the DARPA ORCHID and MESO programs,\nthe Institute for Quantum Information and Matter,\nan NSF Physics Frontiers Center with support of\nthe Gordon and Betty Moore Foundation, and the Kavli\nNanoscience Institute at Caltech. ASN acknowledges\nsupport from NSERC. SG was supported by a Marie\nCurie International Outgoing Fellowship within the 7th\nEuropean Community Framework Programme.\n\nSubmitted - 1403.3703v1.pdf
", "abstract": "Optical measurements of a nanoscale silicon optomechanical crystal cavity with a mechanical resonance\nfrequency of 3.6 GHz are performed at sub-kelvin temperatures. We infer optical-absorption-induced\nheating and damping of the mechanical resonator from measurements of phonon occupancy and motional sideband asymmetry. At the lowest probe power and lowest fridge temperature(T_f = 10 mK), the localized mechanical resonance is found to couple at a rate of \u03b3_i/2\u03c0 = 400 Hz\n(Q_m = 9 x 10^6) to a thermal bath of temperature T_b \u2248 270 mK. These measurements indicate that silicon optomechanical crystals cooled to millikelvin temperatures should be suitable for a variety of experiments involving coherent coupling between photons and phonons at the single quanta level.", "date": "2014-03-14", "date_type": "published", "id_number": "CaltechAUTHORS:20140402-105840104", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140402-105840104", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Advanced Research Projects Agency (DARPA)" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Marie Curie Fellowship" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1403.3703", "primary_object": { "basename": "1403.3703v1.pdf", "url": "https://authors.library.caltech.edu/records/aq0vm-7x550/files/1403.3703v1.pdf" }, "pub_year": "2014", "author_list": "Meenehan, Se\u00e1n M.; Cohen, Justin D.; et el." }, { "id": "https://authors.library.caltech.edu/records/f9txd-6jq82", "eprint_id": 43591, "eprint_status": "archive", "datestamp": "2023-08-19 14:18:46", "lastmod": "2023-10-25 23:41:32", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Arad-Itai", "name": { "family": "Arad", "given": "Itai" } }, { "id": "Kitaev-A", "name": { "family": "Kitaev", "given": "Alexei" } }, { "id": "Landau-Zeph", "name": { "family": "Landau", "given": "Zeph" } }, { "id": "Vazirani-Umesh-V", "name": { "family": "Vazirani", "given": "Umesh" } } ] }, "title": "An area law and sub-exponential algorithm for 1D systems", "ispublished": "unpub", "full_text_status": "public", "note": "We are grateful to Dorit Aharonov, Fernando Brandao, and Matt Hastings for inspiring discussions\nabout the above and related topics.\n\nSubmitted - 1301.1162v1.pdf
", "abstract": "We give a new proof for the area law for general 1D gapped systems, which exponentially improves Hastings' famous result [1]. Specifically, we show that for a chain of d-dimensional spins, governed by a 1D local Hamiltonian with a spectral gap \u03b5 > 0, the entanglement entropy of the ground state with respect to any cut in the chain is upper bounded by O(log^3 d/\u03b5 ). Our approach uses the framework of Refs. [2, 3] to construct a Chebyshev-based AGSP (Approximate Ground Space Projection) with favorable factors. However, our construction uses the Hamiltonian directly, instead of using the Detectability lemma, which allows us to work with general (frustrated) Hamiltonians, as well as slightly improving the 1/\u03b5 dependence of the bound in Ref. [3]. To achieve that, we establish a new, \"random-walk like\", bound on the entanglement rank of an arbitrary power of a 1D Hamiltonian, which might be of independent interest: ER(H^\u2113) \u2264 (\u2113d)O(\u221a\u2113). Finally, treating d as a constant, our AGSP shows that the ground state is well approximated by a matrix product state with a sublinear bond dimension B = \u03b5 ^O(log^(3/4) n/\u03b5^(1/4)). Using this in conjunction with known dynamical programing algorithms, yields an algorithm for a 1=poly(n) approximation of the ground energy with a subexponential running time T \u2264 exp (\u03b5O(log^(3/4) n/\u03b5^(1/4))).", "date": "2014-01-30", "date_type": "published", "id_number": "CaltechAUTHORS:20140130-142058060", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140130-142058060", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1301.1162v1", "primary_object": { "basename": "1301.1162v1.pdf", "url": "https://authors.library.caltech.edu/records/f9txd-6jq82/files/1301.1162v1.pdf" }, "pub_year": "2014", "author_list": "Arad, Itai; Kitaev, Alexei; et el." }, { "id": "https://authors.library.caltech.edu/records/4v7ef-5r378", "eprint_id": 41520, "eprint_status": "archive", "datestamp": "2023-08-19 21:04:35", "lastmod": "2023-10-24 23:48:22", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gu-Zheng-Cheng", "name": { "family": "Gu", "given": "Zheng-Cheng" } } ] }, "title": "Majorana ghosts: From topological superconductor to the origin of neutrino masses, three generations and their mass mixing", "ispublished": "unpub", "full_text_status": "public", "note": "Z-C Gu thank T.K. Ng's invitation for IAS Program on Topological Materials and Strongly Correlated Electronic Systems at HKUST, where the work was initiated, and Henry\nTye, K.T. Law, Z-X Liu, T. Liu for helpful discussions on early results. Z-C Gu especially thank John Preskill, Alexei Kitaev's encourages and delightful discussions for this work. Z-C Gu also thank X-G Wen, Y-S Wu, D. Gaiotto's suggestions for improving presentations, and his wife Y-F Ge's help on investigating experiment results. This work is supported in part by the Gordon and Betty Moore Foundation.\n\nSubmitted - 1308.2488v1.pdf
", "abstract": "The existence of three generations of neutrinos and their mass mixing are the deep mysteries of our universe. The history of neutrino physics can be traced back to Majorana's elegant work on a real solution of the Dirac equation known as the Majorana fermion. A cutting-edge step towards understanding the nature of neutrino has been taken by the experimental discovery of neutrino mass mixing during the past decade, which indicates neutrino has a small but non-vanishing mass. A natural way to explain the origin of this small mass is the so-called seesaw mechanism, which requires the neutrino to be a Majorana fermion. Recently, Majorana's spirit returns in modern\ncondensed matter physics-in the context of Majorana zero modes in certain classes of topological superconductors(TSCs). In this paper, we attempt to investigate the topological nature of the neutrino by establishing a connection between the Majorana fermion and Majorana zero modes assuming a relativistic Majorana fermion is made up of four Majorana zero modes. We begin with an exactly solvable 1D condensed matter model which realizes a T^2 = -1 time reversal symmetry protected TSC. We show that the pair of Majorana zero modes on each end will realize a T^4 = -1 representation of the time reversal symmetry and carry 1/4 spin. We find that a pair of Majorana\nzero modes can realize a P^4 = -1 parity symmetry as well and even a nontrivial C^4 = -1 charge conjugation symmetry. The CPT symmetries for a Majorana fermion made up of four Majorana modes form a super algebra. We then generalize the CPT super algebra into quantum field theory and point out that the nontrivial charge conjugation symmetry can be promoted to a Z_2 gauge symmetry, whose spontaneously breaking leads to the origin of the (right-handed) neutrino mass. The Z_2 gauge symmetry indicates the existence of the fifth force in our universe, which is possible to be detected in future LHC experiment. Finally, we show that the origin of three generations of neutrinos can be naturally explained as three distinguishable ways to form a pair of complex fermions(a particle and an anti-particle) out of four Majorana zero modes, characterized by the\nT^4 = -1, (TP)^4 = -1 and (TC)^4 = -1 fractionalized symmetries that particles/anti-particles carry. Together with the Z_2 gauge (minimal coupling) principle, we are able to determine the mass mixing matrix with no fitting parameter at leading order(in the absence of the CP violation and charged lepton contribution). We obtain \u03b8_(12) = 31.7\u00ba; \u03b8_(23) = \u03b845\u00ba and \u03b8_(13) = 0\u00ba(known as the golden\nratio pattern), which are intrinsically close to the current experimental results. We further predict\nan exact mass ratio for the three mass eigenstates with m_1/m_3 = m_2/m_3 = 3/\u221a5.", "date": "2013-09-25", "date_type": "published", "id_number": "CaltechAUTHORS:20130925-103447828", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130925-103447828", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Gordon and Betty Moore Foundation" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1308.2488", "primary_object": { "basename": "1308.2488v1.pdf", "url": "https://authors.library.caltech.edu/records/4v7ef-5r378/files/1308.2488v1.pdf" }, "pub_year": "2013", "author_list": "Gu, Zheng-Cheng" }, { "id": "https://authors.library.caltech.edu/records/a51pt-ev937", "eprint_id": 43174, "eprint_status": "archive", "datestamp": "2023-08-19 20:29:24", "lastmod": "2023-10-25 23:20:13", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Safavi-Naeini-A-H", "name": { "family": "Safavi-Naeini", "given": "Amir H." }, "orcid": "0000-0001-6176-1274" }, { "id": "Painter-O", "name": { "family": "Painter", "given": "Oskar" }, "orcid": "0000-0002-1581-9209" } ] }, "title": "Comment on \"A classical model for asymmetric sidebands in cavity optomechanical measurements\"", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted June 22, 2013.\n\nThe authors would like to thank K. Lenhert, D.\nStamper-Kurn, H. Miao, K. Hammerer, and Y. Chen for\ninsightful conversations. This work was supported by the\nDARPA/MTO ORCHID program through a grant from\nAFOSR, by the Institute for Quantum Information and\nMatter, an NSF Physics Frontiers Center with support\nof the Gordon and Betty Moore Foundation, and the\nKavli Nanoscience Institute at Caltech. ASN acknowledges support from NSERC.\n\nSubmitted - Painter.pdf
", "abstract": "We respond to a recent manuscript by Tsang [arXiv:1306.2699\n], on whether the measurement presented in Safavi-Naeini et al. [Phys. Rev. Lett. 108, 033 602 (2012)] can be explained \"withoutreference to quantum mechanics\". We show that the fully classical analysis provided by Tsang, and previously by Safavi-Naeini et al. [New J. Phys. 15, 035007 (2013)], has been ruled out by our published data. In addition, we discuss the role of the mathematical formulation used on the\ninterpretation of the asymmetry effect, as has previously been considered by Khalili et al. [Phys.\nRev. A 86, 033840 (2012)", "date": "2013-06-25", "date_type": "published", "id_number": "CaltechAUTHORS:20140102-104155905", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140102-104155905", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Institute of Quantum Information and Matter (IQIM)" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.48550/arXiv.1306.5309", "primary_object": { "basename": "Painter.pdf", "url": "https://authors.library.caltech.edu/records/a51pt-ev937/files/Painter.pdf" }, "pub_year": "2013", "author_list": "Safavi-Naeini, Amir H. and Painter, Oskar" }, { "id": "https://authors.library.caltech.edu/records/kmjbn-35b51", "eprint_id": 43585, "eprint_status": "archive", "datestamp": "2023-08-19 19:00:45", "lastmod": "2024-01-13 06:05:50", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schulman-L-J", "name": { "family": "Schulman", "given": "Leonard J." }, "orcid": "0000-0001-9901-2797" } ] }, "title": "An MQ/Code Cyptosystem Proposal", "ispublished": "unpub", "full_text_status": "restricted", "keywords": "Multivariate quadratic cryptosystem, MinRank, tensor decomposition, post-\nquantum cryptography, code-based cryptography", "note": "Received March 6, 2013.\n\nThanks to the organizers of post-quantum cryptography workshops at Dagstuhl and the Lorentz\nCenter for creating stimulating environments in which some of these ideas were developed. I am\ngrateful to the participants of those meetings, in particular Enrico Thomae, for comments. Thanks\nalso to Alex Vardy, Madhu Sudan, Venkat Guruswami and Zvika Brakerski for helpful discussions", "abstract": "We describe a new trap-door (and PKC) proposal. The proposal is ``multivariate quadratic'' (relies on the hardness of solving systems of quadratic equations); it is also code-based, and uses the code-scrambling technique of McEliece (1978). However, in the new proposal, the error-correcting code is not revealed in the public key, which protects against the leading attacks on McEliece's method.", "date": "2013-03-06", "date_type": "published", "publisher": "Caltech Library", "id_number": "CaltechAUTHORS:20140130-133600557", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140130-133600557", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" } ] }, "pub_year": "2013", "author_list": "Schulman, Leonard J." }, { "id": "https://authors.library.caltech.edu/records/wdttr-ypf07", "eprint_id": 36716, "eprint_status": "archive", "datestamp": "2023-08-19 13:32:18", "lastmod": "2023-10-23 15:25:14", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "M\u00fcller-Ebhardt-H", "name": { "family": "M\u00fcller-Ebhardt", "given": "Helge" } }, { "id": "Miao-H", "name": { "family": "Miao", "given": "Haixing" } }, { "id": "Danilishin-S", "name": { "family": "Danilishin", "given": "Stefan" } }, { "id": "Chen-Yanbei", "name": { "family": "Chen", "given": "Yanbei" }, "orcid": "0000-0002-9730-9463" } ] }, "title": "Quantum-state steering in optomechanical devices", "ispublished": "unpub", "full_text_status": "public", "note": "Imported from arXiv.\n\nAcknowledgments. We thank all the members of the AEI Caltech-\nMIT MQM group for fruitful discussions. This research\nis supported by the Alexander von Humboldt Foundation's\nSofja Kovalevskaja Programme, NSF grants PHY-\n0956189 and PHY-1068881, the David and Barbara Groce\nstartup fund at Caltech, as well as the Institute for Quantum\nInformation and Matter, a Physics Frontier Center with funding\nfrom the National Science Foundation and the Gordon and\nBetty Moore Foundation.\n\nSubmitted - 1211.4315.pdf
", "abstract": "We show that optomechanical systems in the quantum regime can be used to\ndemonstrate EPR-type quantum entanglement between the optical field and the\nmechanical oscillator, via quantum-state steering. Namely, the conditional\nquantum state of the mechanical oscillator can be steered into different\nquantum states depending the choice made on which quadrature of the out-going\nfield is to be measured via homodyne detection. More specifically, if quantum\nradiation pressure force dominates over thermal force, the oscillator's quantum\nstate is steerable with a photodetection efficiency as low as 50%, approaching\nthe ideal limit shown by Wiseman and Gambetta [Phys. Rev. Lett. 108,\n220402 (2012)]. We also show that requirement for steerability is the same as\nthose for achieving sub-Heisenberg state tomography using the same experimental\nsetup.", "date": "2013-02-13", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20130131-140930189", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130131-140930189", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Alexander von Humboldt Foundation's Sofja Kovalevskaja Programme" }, { "agency": "NSF", "grant_number": "PHY-1068881" }, { "agency": "NSF", "grant_number": "PHY- 0956189" }, { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation" } ] }, "local_group": { "items": [ { "id": "TAPIR" }, { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1211.4315v1", "primary_object": { "basename": "1211.4315.pdf", "url": "https://authors.library.caltech.edu/records/wdttr-ypf07/files/1211.4315.pdf" }, "pub_year": "2013", "author_list": "M\u00fcller-Ebhardt, Helge; Miao, Haixing; et el." }, { "id": "https://authors.library.caltech.edu/records/ngjvk-36z58", "eprint_id": 35259, "eprint_status": "archive", "datestamp": "2023-08-19 08:43:11", "lastmod": "2023-10-20 15:54:27", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Huan", "name": { "family": "Yang", "given": "Huan" } }, { "id": "Miao-Haixing", "name": { "family": "Miao", "given": "Haixing" }, "orcid": "0000-0003-2879-5821" }, { "id": "Chen-Yanbei", "name": { "family": "Chen", "given": "Yanbei" }, "orcid": "0000-0002-9730-9463" } ] }, "title": "Reveal non-Markovianity of open quantum systems via local operations", "ispublished": "unpub", "full_text_status": "public", "note": "We thank S.L. Danilishin, F.Ya,\nKahlili and other colleagues in the LIGO MQM group\nfor fruitful discussions. This work has been supported by\nNSF grants PHY-0555406, PHY-0653653, PHY-0601459,\nPHY-0956189, PHY-1068881, as well as the David and\nBarbara Groce startup fund at Caltech.\n\nSubmitted - 1111.6079v1.pdf
", "abstract": "Non-Markovianity, as an important feature of general open quantum systems, is usually difficult to quantify with limited knowledge of how the plant that we are interested in interacts with its environment-the bath. It often happens that the reduced dynamics of the plant attached to a non-Markovian bath becomes indistinguishable from the one with a Markovian bath, if we left the entire system freely evolve. Here we show that non-Markovianity can be revealed via applying local unitary operations on the plant-they will influence the plant evolution at later times due to memory of the bath. This not only provides a new criterion for non-Markovianity, but also sheds light on protecting and recovering quantum coherence in non-Markovian systems, which will be useful for quantum-information processing.", "date": "2012-11-03", "date_type": "published", "id_number": "CaltechAUTHORS:20121102-100208411", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121102-100208411", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-0555406" }, { "agency": "NSF", "grant_number": "PHY-0653653" }, { "agency": "NSF", "grant_number": "PHY-0601459" }, { "agency": "NSF", "grant_number": "PHY-0956189" }, { "agency": "NSF", "grant_number": "PHY-1068881" }, { "agency": "David and Lucile Packard Foundation" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "TAPIR" } ] }, "doi": "10.48550/arXiv.1111.6079", "primary_object": { "basename": "1111.6079v1.pdf", "url": "https://authors.library.caltech.edu/records/ngjvk-36z58/files/1111.6079v1.pdf" }, "pub_year": "2012", "author_list": "Yang, Huan; Miao, Haixing; et el." }, { "id": "https://authors.library.caltech.edu/records/sx3hc-h1t43", "eprint_id": 35271, "eprint_status": "archive", "datestamp": "2023-08-19 11:29:11", "lastmod": "2023-10-20 15:55:08", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Michalakis-S", "name": { "family": "Michalakis", "given": "Spyridon" }, "orcid": "0000-0003-4963-1156" } ] }, "title": "Stability of the Area Law for the Entropy of Entanglement", "ispublished": "unpub", "full_text_status": "public", "note": "The author would like to thank M. B. Hastings for helpful remarks on the use of quasi-adiabatic\nevolution in the context of entanglement entropy, as well as fruitful discussions with B. Nachtergaele, N. Schuch and\nA. Gorshkov.\n\nSubmitted - 1206.6900v2.pdf
", "abstract": "Recent results on the stability of the spectral gap under general perturbations for frustration-free Hamiltonians, have motivated the following question: Does the entanglement entropy of quantum states that are connected to states satisfying an area law along gapped Hamiltonian paths, also satisfy an area law? We answer this question in the affirmative, combining recent advances in quasi-adiabatic evolution and Lieb-Robinson bounds with ideas from the proof of the 1D area law.", "date": "2012-11-03", "date_type": "published", "id_number": "CaltechAUTHORS:20121102-135530255", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121102-135530255", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1206.6900", "primary_object": { "basename": "1206.6900v2.pdf", "url": "https://authors.library.caltech.edu/records/sx3hc-h1t43/files/1206.6900v2.pdf" }, "pub_year": "2012", "author_list": "Michalakis, Spyridon" }, { "id": "https://authors.library.caltech.edu/records/tf8r6-qs172", "eprint_id": 32421, "eprint_status": "archive", "datestamp": "2023-08-19 10:37:37", "lastmod": "2023-10-17 23:48:25", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kitaev-A", "name": { "family": "Kitaev", "given": "Alexei" } }, { "id": "Wang-Zhenghan", "name": { "family": "Wang", "given": "Zhenghan" }, "orcid": "0000-0002-5253-6400" } ] }, "title": "Solutions to generalized Yang-Baxter equations via ribbon fusion categories", "ispublished": "unpub", "full_text_status": "public", "note": "The second author is partially supported by NSF DMS 1108736 and would like to thank E.\nRowell for observing (3) of Thm. 2.5, S. Hong for helping on 6j symbols, and R. Chen for\nnumerically testing the solutions.\n\nSubmitted - 1203.1063v2.pdf
", "abstract": "Inspired by quantum information theory, we look for representations of the braid groups B_n on V^(\u2297(n+m\u22122)) for some fixed vector space V such\nthat each braid generator \u03c3_i, i = 1, ..., n\u22121, acts on m consecutive tensor factors\nfrom i through i +m\u22121. The braid relation for m = 2 is essentially the Yang-Baxter equation, and the cases for m > 2 are called generalized Yang-Baxter\nequations. We observe that certain objects in ribbon fusion categories naturally give rise to such representations for the case m = 3. Examples are given\nfrom the Ising theory (or the closely related SU(2)_2), SO(N)_2 for N odd, and\nSU(3)_3. The solution from the Jones-Kauffman theory at a 6th root of unity,\nwhich is closely related to SO(3)_2 or SU(2)_4, is explicitly described in the end.", "date": "2012-07-19", "date_type": "published", "id_number": "CaltechAUTHORS:20120713-102318475", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120713-102318475", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMS-1108736" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1203.1063", "primary_object": { "basename": "1203.1063v2.pdf", "url": "https://authors.library.caltech.edu/records/tf8r6-qs172/files/1203.1063v2.pdf" }, "pub_year": "2012", "author_list": "Kitaev, Alexei and Wang, Zhenghan" }, { "id": "https://authors.library.caltech.edu/records/8qd5x-9v245", "eprint_id": 32406, "eprint_status": "archive", "datestamp": "2023-08-22 05:38:26", "lastmod": "2023-10-17 23:47:59", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schulman-L-J", "name": { "family": "Schulman", "given": "Leonard J." }, "orcid": "0000-0001-9901-2797" } ] }, "title": "Cryptography from tensor problems", "ispublished": "unpub", "full_text_status": "restricted", "keywords": "Multivariate quadratic cryptosystem, MinRank, tensor rank, post-quantum cryptography", "note": "Supported in part by the NSF.\nThanks to Oded Regev, Yi-Kai Liu and Aram Harrow for helpful comments. Thanks also to the\norganizers of a 2011 Dagstuhl workshop on post-quantum cryptography, which helped stimulate\nthis work.", "abstract": "We describe a new proposal for a trap-door one-way function. The new proposal belongs to the \"multivariate quadratic\" family but the trap-door is different from existing methods, and is simpler.", "date": "2012-07-19", "date_type": "published", "publisher": "Caltech Library", "id_number": "CaltechAUTHORS:20120713-075312396", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120713-075312396", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "pub_year": "2012", "author_list": "Schulman, Leonard J." }, { "id": "https://authors.library.caltech.edu/records/7rhg8-ypf09", "eprint_id": 32435, "eprint_status": "archive", "datestamp": "2023-08-19 08:04:33", "lastmod": "2023-10-17 23:48:57", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-I-H", "name": { "family": "Kim", "given": "Isaac H." } } ] }, "title": "Stability of topologically invariant order parameters at finite temperature", "ispublished": "unpub", "full_text_status": "public", "note": "This research was supported in part by NSF under\nGrant No. PHY-0803371, by ARO Grant No. W911NF-09-1-0442, and DOE Grant No. DE-FG03-92-ER40701.\nI thank Steve Flammia, Jeongwan Haah, and Spyridon\nMichalakis for helpful discussions.\n\nSubmitted - 1109.3496v1.pdf
", "abstract": "Topological entanglement entropy is a topological invariant which can detect topological order of quantum many-body ground state. We assume an existence of such order parameter at finite temperature which is invariant under smooth deformation of the subsystems, and study its stability under hamiltonian perturbation. We apply this assumption to a Gibbs state of hamiltonian which satisfies so called `strong commuting' condition, which we shall define in the paper. Interesting models in this category include local hamiltonian models based on quantum error correcting code. We prove a stability of such topologically invariant order parameter against arbitrary perturbation which can be expressed as a sum of geometrically local bounded-norm terms. The first order correction against such perturbation vanishes in the thermodynamic limit.", "date": "2012-07-19", "date_type": "published", "id_number": "CaltechAUTHORS:20120713-140540112", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120713-140540112", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-0803371" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-09-1-0442" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG03-92-ER40701" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1109.3496v1", "primary_object": { "basename": "1109.3496v1.pdf", "url": "https://authors.library.caltech.edu/records/7rhg8-ypf09/files/1109.3496v1.pdf" }, "pub_year": "2012", "author_list": "Kim, Isaac H." }, { "id": "https://authors.library.caltech.edu/records/1a3ke-r5249", "eprint_id": 32410, "eprint_status": "archive", "datestamp": "2023-08-19 09:43:35", "lastmod": "2023-10-17 23:48:04", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-I-H", "name": { "family": "Kim", "given": "Isaac H." } } ] }, "title": "3D local qupit quantum code without string logical operator", "ispublished": "unpub", "full_text_status": "public", "note": "This research was supported in part by NSF under\nGrant No. PHY-0803371, by ARO Grant No. W911NF-09-1-0442, and DOE Grant No. DE-FG03-92-ER40701.\nAuthor would like to thank Steven Flammia, Jeongwan\nHaah, Robert Koenig, and John Preskill for useful dis-\ncussions.\n\nSubmitted - 1202.0052v1.pdf
", "abstract": "Recently Haah introduced a new quantum error correcting code embedded on a cubic lattice. One of the defining properties of this code is the absence of string logical operator. We present new codes with similar properties by relaxing the condition on the local particle dimension. The resulting code is well-defined when the local Hilbert space dimension is prime. These codes can be divided into two different classes: the local stabilizer generators are either symmetric or antisymmetric with respect to the inversion operation. These is a nontrivial correspondence between these two classes. For any symmetric code without string logical operator, there exists a complementary antisymmetric code with the same property and vice versa. We derive a sufficient condition for the absence of string logical operator in terms of the algebraic constraints on the defining parameters of the code. Minimal number of local particle dimension which satisfies the condition is 5. These codes have logarithmic energy barrier for any logical error.", "date": "2012-07-19", "date_type": "published", "id_number": "CaltechAUTHORS:20120713-091419180", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120713-091419180", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-0803371" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-09-1-0442" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG03-92-ER40701" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1202.0052v1", "primary_object": { "basename": "1202.0052v1.pdf", "url": "https://authors.library.caltech.edu/records/1a3ke-r5249/files/1202.0052v1.pdf" }, "pub_year": "2012", "author_list": "Kim, Isaac H." }, { "id": "https://authors.library.caltech.edu/records/s2ccp-2z894", "eprint_id": 32408, "eprint_status": "archive", "datestamp": "2023-08-19 06:52:58", "lastmod": "2023-10-17 23:48:01", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jordan-S-P", "name": { "family": "Jordan", "given": "Stephen P." } }, { "id": "Alagic-G", "name": { "family": "Alagic", "given": "Gorjan" } } ] }, "title": "Approximating the Turaev-Viro Invariant of Mapping Tori is Complete for One Clean Qubit", "ispublished": "unpub", "full_text_status": "public", "note": "This work was done at Institute for Quantum Information, Caltech.\n\nSubmitted - 1105.5100v2.pdf
", "abstract": "The Turaev-Viro invariants are scalar topological invariants of three-dimensional manifolds. Here we show that the problem of estimating the Fibonacci version of the Turaev-Viro invariant of a mapping torus is a complete problem for the one clean qubit complexity class (DQC1). This complements a previous result showing that estimating the Turaev-Viro invariant for arbitrary manifolds presented as Heegaard splittings is a complete problem for the standard quantum computation model (BQP). We also discuss a beautiful analogy between these results and previously known results on the computational complexity of approximating the Jones polynomial.", "date": "2012-07-19", "date_type": "published", "id_number": "CaltechAUTHORS:20120713-083236942", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120713-083236942", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.48550/arXiv.1105.5100", "primary_object": { "basename": "1105.5100v2.pdf", "url": "https://authors.library.caltech.edu/records/s2ccp-2z894/files/1105.5100v2.pdf" }, "pub_year": "2012", "author_list": "Jordan, Stephen P. and Alagic, Gorjan" }, { "id": "https://authors.library.caltech.edu/records/yxrwz-hb086", "eprint_id": 29151, "eprint_status": "archive", "datestamp": "2023-08-19 09:38:08", "lastmod": "2023-10-24 18:24:09", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Jiang", "name": { "family": "Li", "given": "Jiang" } }, { "id": "Lee-Hansuek", "name": { "family": "Lee", "given": "Hansuek" }, "orcid": "0000-0002-0748-7662" }, { "id": "Chen-Tong", "name": { "family": "Chen", "given": "Tong" } }, { "id": "Painter-O", "name": { "family": "Painter", "given": "Oskar" }, "orcid": "0000-0002-1581-9209" }, { "id": "Vahala-K-J", "name": { "family": "Vahala", "given": "Kerry J." }, "orcid": "0000-0003-1783-1380" } ] }, "title": "Chip-based Brillouin lasers as spectral purifiers for photonic systems", "ispublished": "unpub", "full_text_status": "public", "keywords": "Optics (physics.optics)", "note": "The authors would like to thank\nScott Papp and Scott Diddams for helpful comments. We\ngratefully acknowledge the Defense Advanced Research\nProjects Agency under the Orchid programs and also the\nKavli Nanoscience Institute at Caltech.\n\nSubmitted - 1201.4212v1.pdf
", "abstract": "High coherence lasers are essential in a wide range of applications, however, such performance is normally associated with large laser cavities, because increasing energy storage reduces quantum phase noise and also renders the laser frequency less sensitive to cavity vibration. This basic scaling rule is at odds with an emerging set of optical systems that place focus on compact (optimally integrable) sources of high coherence light. These include phase-coherent optical communication using quadrature-amplitude-modulation, and also record-low phase noise microwave sources based upon optical comb techniques. In this work, the first, chip-based Brillouin laser is demonstrated. It features high-efficiency and single-line operation with the smallest recorded Schawlow-Townes frequency noise for any chip-based laser. Because the frequency offset between the laser's emission and the input pump is relatively small, the device provides a new function: spectral purification of compact, low coherence sources such as semiconductor lasers.", "date": "2012-04-24", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20120206-105450544", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120206-105450544", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Advanced Research Projects Agency (DARPA)" }, { "agency": "Kavli Nanoscience Institute" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.48550/arXiv.1201.4212", "primary_object": { "basename": "1201.4212v1.pdf", "url": "https://authors.library.caltech.edu/records/yxrwz-hb086/files/1201.4212v1.pdf" }, "pub_year": "2012", "author_list": "Li, Jiang; Lee, Hansuek; et el." } ]