[ { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xzrcg-q7w19", "eprint_status": "archive", "datestamp": "2024-02-21 19:27:35", "lastmod": "2024-02-21 19:27:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kar-Uddipta", "name": { "family": "Kar", "given": "Uddipta" } }, { "id": "Lu-Elisha-Cho-Hao", "name": { "family": "Lu", "given": "Elisha Cho-Hao" } }, { "id": "Singh-Akhilesh-Kr", "name": { "family": "Singh", "given": "Akhilesh Kr." } }, { "id": "Peram-Venkata-Sreenivasa-Reddy", "name": { "family": "Reddy", "given": "P.\u2009V. Sreenivasa" }, "orcid": "0000-0003-1460-342X" }, { "id": "Han-Youngjoon", "name": { "family": "Han", "given": "Youngjoon" }, "orcid": "0000-0003-1256-9328" }, { "id": "Li-Xinwei", "name": { "family": "Li", "given": "Xinwei" } }, { "id": "Cheng-Cheng-Tung", "name": { "family": "Cheng", "given": "Cheng-Tung" }, "orcid": "0000-0002-9117-5783" }, { "id": "Yang-Song", "name": { "family": "Yang", "given": "Song" }, "orcid": "0000-0003-4296-8856" }, { "id": "Lin-Chun-Yen", "name": { "family": "Lin", "given": "Chun-Yen" }, "orcid": "0000-0002-5083-9256" }, { "id": "Cheng-I-Chun", "name": { "family": "Cheng", "given": "I-Chun" }, "orcid": "0000-0003-2209-3298" }, { "id": "Hsu-Chia-Hung", "name": { "family": "Hsu", "given": "Chia-Hung" }, "orcid": "0009-0002-7087-4718" }, { "id": "Hsieh-D", "name": { "family": "Hsieh", "given": "David" }, "orcid": "0000-0002-0812-955X" }, { "id": "Lee-Wei-Cheng", "name": { "family": "Lee", "given": "Wei-Cheng" }, "orcid": "0000-0002-6140-6448" }, { "id": "Guo-Guang-Yu", "name": { "family": "Guo", "given": "Guang-Yu" }, "orcid": "0000-0003-3097-0916" }, { "id": "Lee-Wei-Li", "name": { "family": "Lee", "given": "Wei-Li" }, "orcid": "0000-0001-7207-1607" } ] }, "title": "Nonlinear and Nonreciprocal Transport Effects in Untwinned Thin Films of Ferromagnetic Weyl Metal SrRuO\u2083", "ispublished": "pub", "full_text_status": "public", "keywords": "General Physics and Astronomy", "note": "
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.
\n\n \n\nU. K., E. C.-H. L., C.-T. C., I-C. C., and W.-L. L. carried out the low-temperature magnetotransport measurements and data analyses. U.K. and A. K. S. grew the epitaxial SRO films. A. K. S., S. Y., C.-Y. L., and C.-H. H. performed the x-ray measurements at NSRRC in Taiwan. P. V. S. R., G.-Y. G., and W.-C. L. performed the ab initio calculations. Y. H., X. L., and D. H. performed the SHG measurements and analyses. G.-Y. G. and W.-L. L. designed the experiment and wrote the manuscript.
\n\nThe authors declare no competing financial or nonfinancial interests.
\n\n ", "abstract": "The identification of distinct charge transport features, deriving from nontrivial bulk band and surface states, has been a challenging subject in the field of topological systems. In topological Dirac and Weyl semimetals, nontrivial conical bands with Fermi-arc surface states give rise to negative longitudinal magnetoresistance due to chiral anomaly effect and unusual thickness dependent quantum oscillation from Weyl-orbit effect, which were demonstrated recently in experiments. In this work, we report the experimental observations of large nonlinear and nonreciprocal transport effects for both longitudinal and transverse channels in an untwinned Weyl metal of SrRuO\u2083 thin film grown on a SrTiO\u2083 substrate. From rigorous measurements with bias current applied along various directions with respect to the crystalline principal axes, the magnitude of nonlinear Hall signals from the transverse channel exhibits a simple sinα dependence at low temperatures, where α is the angle between bias current direction and orthorhombic [001]\u2092, reaching a maximum when current is along orthorhombic [1¯10]\u2092. On the contrary, the magnitude of nonlinear and nonreciprocal signals in the longitudinal channel attains a maximum for bias current along [001]o, and it vanishes for bias current along [1¯10]\u2092. The observed α-dependent nonlinear and nonreciprocal signals in longitudinal and transverse channels reveal a magnetic Weyl phase with an effective Berry curvature dipole along [1¯10]\u2092 from surface states, accompanied by 1D chiral edge modes along [001]\u2092.
", "date": "2024-01", "date_type": "published", "publication": "Physical Review X", "volume": "14", "number": "1", "publisher": "American Physical Society", "pagerange": "011022", "issn": "2160-3308", "official_url": "https://authors.library.caltech.edu/records/xzrcg-q7w19", "funders": { "items": [ { "grant_number": "108-2628-M-001-007-MY3" }, { "grant_number": "110-2112-M-002-030-MY3" }, { "grant_number": "111-2112-M-001-056-MY3" }, {}, { "grant_number": "AS-NTU-110-10" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.1103/physrevx.14.011022", "primary_object": { "basename": "PhysRevX.14.011022.pdf", "url": "https://authors.library.caltech.edu/records/xzrcg-q7w19/files/PhysRevX.14.011022.pdf" }, "related_objects": [ { "basename": "main_wlee_SOM_v6.pdf", "url": "https://authors.library.caltech.edu/records/xzrcg-q7w19/files/main_wlee_SOM_v6.pdf" } ], "resource_type": "article", "pub_year": "2024", "author_list": "Kar, Uddipta; Lu, Elisha Cho-Hao; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/b8j5v-rrk37", "eprint_status": "archive", "datestamp": "2023-12-13 22:43:13", "lastmod": "2023-12-13 22:43:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ning-Honglie", "name": { "family": "Ning", "given": "Honglie" }, "orcid": "0000-0003-4867-0751" }, { "id": "Mehio-Omar", "name": { "family": "Mehio", "given": "Omar" }, "orcid": "0000-0001-7923-2178" }, { "id": "Li-Xinwei", "name": { "family": "Li", "given": "Xinwei" }, "orcid": "0000-0003-0555-2624" }, { "id": "Buchhold-Michael", "name": { "family": "Buchhold", "given": "Michael" }, "orcid": "0000-0001-5194-9388" }, { "id": "Driesse-Mathias", "name": { "family": "Driesse", "given": "Mathias" }, "orcid": "0000-0002-3983-5852" }, { "id": "Zhao-Hengdi", "name": { "family": "Zhao", "given": "Hengdi" }, "orcid": "0000-0003-4606-6323" }, { "id": "Cao-Gang", "name": { "family": "Cao", "given": "Gang" }, "orcid": "0000-0001-9779-430X" }, { "id": "Hsieh-D", "name": { "family": "Hsieh", "given": "David" }, "orcid": "0000-0002-0812-955X" } ] }, "title": "A coherent phonon-induced hidden quadrupolar ordered state in Ca\u2082RuO\u2084", "ispublished": "pub", "full_text_status": "public", "keywords": "General Physics and Astronomy; General Biochemistry, Genetics and Molecular Biology; General Chemistry; Multidisciplinary", "note": "\u00a9 The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
\n\nWe thank Min-Cheol Lee and Jong-Seok Lee for sharing optical conductivity data. Time-resolved optical spectroscopy measurements and model Hamiltonian calculations were supported by an ARO PECASE Award No. W911NF-17-1-0204. D.H. acknowledges support for instrumentation from the David and Lucile Packard Foundation and the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (PHY-1733907). M.B. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy Cluster of Excellence Matter and Light for Quantum Computing (ML4Q) EXC 2004/1 390534769, and by the DFG Collaborative Research Center (CRC) 1238 (Project No. 277146847, subproject C04) and CRC 183 (Project No. 277101999, subproject B02). Work at C.U. Boulder is supported by the National Science Foundation via Grant No. DMR 2204811.
\n\nThese authors contributed equally: Honglie Ning, Omar Mehio, Xinwei Li.
H.N., X.L, O.M., and D.H. conceived the experiment. X.L. and H.N. performed the coherent phonon spectroscopy measurements. H.N. and M.B. developed the many-body theory and conducted the dynamical simulations. H.N., X.L, and O.M. analyzed the data. M.D. conducted the DFT simulations. H.Z. and G.C. synthesized and characterized the samples. H.N. and D.H. wrote the manuscript with input from all authors.
\n\nSource data are provided with this paper. All other data that support the findings of this study are available from the corresponding author upon request. Source data are provided with this paper.
\n\nThe authors declare no competing interests.
", "abstract": "AbstractUltrafast laser excitation provides a means to transiently realize long-range ordered electronic states of matter that are hidden in thermal equilibrium. Recently, this approach has unveiled a variety of thermally inaccessible ordered states in strongly correlated materials, including charge density wave, ferroelectric, magnetic, and intertwined charge-orbital ordered states. However, more exotic hidden states exhibiting higher multipolar ordering remain elusive owing to the challenge of directly manipulating and detecting them with light. Here we demonstrate a method to induce a dynamical transition from a thermally allowed to a thermally forbidden spin-orbit entangled quadrupolar ordered state in Ca\u2082RuO\u2084 by coherently exciting a phonon that is strongly coupled to the order parameter. Combining probe photon energy-resolved coherent phonon spectroscopy measurements with model Hamiltonian calculations, we show that the dynamical transition is manifested through anomalies in the temperature, pump excitation fluence, and probe photon energy dependence of the strongly coupled phonon. With this procedure, we introduce a general pathway to uncover hidden multipolar ordered states and to control their re-orientation on ultrashort timescales.
", "date": "2023-12-13", "date_type": "published", "publication": "Nature Communications", "volume": "14", "publisher": "Nature Publishing Group", "pagerange": "8258", "issn": "2041-1723", "official_url": "https://authors.library.caltech.edu/records/b8j5v-rrk37", "funders": { "items": [ { "grant_number": "W911NF-17-1-0204" }, {}, { "grant_number": "PHY-1733907" }, { "grant_number": "EXC 2004/1 390534769" }, { "grant_number": "CRC 1238 277146847-C04" }, { "grant_number": "CRC 183 277101999-B02" }, { "grant_number": "DMR-2204811" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.1038/s41467-023-44021-4", "primary_object": { "basename": "s41467-023-44021-4.pdf", "url": "https://authors.library.caltech.edu/records/b8j5v-rrk37/files/s41467-023-44021-4.pdf" }, "related_objects": [ { "basename": "41467_2023_44021_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/b8j5v-rrk37/files/41467_2023_44021_MOESM1_ESM.pdf" }, { "basename": "41467_2023_44021_MOESM3_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/b8j5v-rrk37/files/41467_2023_44021_MOESM3_ESM.xlsx" } ], "resource_type": "article", "pub_year": "2023", "author_list": "Ning, Honglie; Mehio, Omar; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8v2db-dxg10", "eprint_status": "archive", "datestamp": "2024-01-10 23:56:40", "lastmod": "2024-01-10 23:56:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ron-Alon", "name": { "family": "Ron", "given": "Alon" }, "orcid": "0000-0002-1840-7824" }, { "id": "Ahadi-Kaveh", "name": { "family": "Ahadi", "given": "Kaveh" }, "orcid": "0000-0003-2280-4037" }, { "id": "Hickox-Young-Daniel", "name": { "family": "Hickox-Young", "given": "Daniel" }, "orcid": "0000-0002-5411-0497" }, { "id": "Puggioni-Danilo", "name": { "family": "Puggioni", "given": "Danilo" }, "orcid": "0000-0002-2128-4191" }, { "id": "Mehio-Omar", "name": { "family": "Mehio", "given": "Omar" }, "orcid": "0000-0001-7923-2178" }, { "id": "Rondinelli-James-M", "name": { "family": "Rondinelli", "given": "James M." }, "orcid": "0000-0003-0508-2175" }, { "id": "Stemmer-Susanne", "name": { "family": "Stemmer", "given": "Susanne" }, "orcid": "0000-0002-3142-4696" }, { "id": "Hsieh-D", "name": { "family": "Hsieh", "given": "David" }, "orcid": "0000-0002-0812-955X" } ] }, "title": "Transforming a strain-stabilized ferroelectric into an intrinsic polar metal with light", "ispublished": "pub", "full_text_status": "public", "note": "© 2023 American Physical Society.
\n\nWe explore the effects of chemical doping and photodoping in the strain-induced multiferroic EuTiO\u2083 grown on DyScO\u2083 substrates. The polar order is probed experimentally using second harmonic generation (SHG) and modeled using ab initio calculations. At low photodoping concentrations, we observe a reduction in SHG signal, indicating a destructive coupling between charge carriers and polar order in accordance with our simulations and expectations for a second-order Jahn-Teller driven ferroelectric. However, under increased photodoping the reduction in SHG plateaus at 84% of its original magnitude, indicating resilience of the polar order in the presence of a high concentration of delocalized electrons. This behavior stands in contrast with our first-principles simulations, indicating that EuTiO\u2083 undergoes a transition from ferroelectric to polar metallic character under photodoping. We suggest several hypotheses for the mechanism behind this change in distortion character.
", "date": "2023-12-01", "date_type": "published", "publication": "Physical Review B", "volume": "108", "number": "22", "publisher": "American Physical Society", "pagerange": "224308", "issn": "2469-9950", "official_url": "https://authors.library.caltech.edu/records/8v2db-dxg10", "funders": { "items": [ { "grant_number": "1017/20" }, { "grant_number": "W911NF-16-1-0361" }, { "grant_number": "DMR-1729303" }, { "grant_number": "DMR-1729489" }, { "grant_number": "W911NF-15-1-0017" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.1103/physrevb.108.224308", "primary_object": { "basename": "PhysRevB.108.224308.pdf", "url": "https://authors.library.caltech.edu/records/8v2db-dxg10/files/PhysRevB.108.224308.pdf" }, "related_objects": [ { "basename": "Doped_ETO_on_DSO_Expt_plus_DFT_v3-12.pdf", "url": "https://authors.library.caltech.edu/records/8v2db-dxg10/files/Doped_ETO_on_DSO_Expt_plus_DFT_v3-12.pdf" } ], "resource_type": "article", "pub_year": "2023", "author_list": "Ron, Alon; Ahadi, Kaveh; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/f2wj0-p4753", "eprint_status": "archive", "datestamp": "2023-09-27 22:16:29", "lastmod": "2023-10-05 16:51:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mehio-Omar", "name": { "family": "Mehio", "given": "Omar" }, "orcid": "0000-0001-7923-2178" }, { "id": "Li-Xinwei", "name": { "family": "Li", "given": "Xinwei" }, "orcid": "0000-0003-0555-2624" }, { "id": "Ning-Honglie", "name": { "family": "Ning", "given": "Honglie" }, "orcid": "0000-0003-4867-0751" }, { "id": "Lenar\u010di\u010d-Zala", "name": { "family": "Lenar\u010di\u010d", "given": "Zala" }, "orcid": "0000-0001-8374-8011" }, { "name": { "family": "Han", "given": "Yuchen" } }, { "id": "Buchhold-Michael", "name": { "family": "Buchhold", "given": "Michael" }, "orcid": "0000-0001-5194-9388" }, { "id": "Porter-Zach", "name": { "family": "Porter", "given": "Zach" }, "orcid": "0000-0002-2945-9558" }, { "id": "Laurita-Nicholas-J", "name": { "family": "Laurita", "given": "Nicholas J." } }, { "id": "Wilson-Stephen-D", "name": { "family": "Wilson", "given": "Stephen D." }, "orcid": "0000-0003-3733-930X" }, { "id": "Hsieh-D", "name": { "family": "Hsieh", "given": "David" }, "orcid": "0000-0002-0812-955X" } ] }, "title": "A Hubbard exciton fluid in a photo-doped antiferromagnetic Mott insulator", "ispublished": "pub", "full_text_status": "public", "keywords": "General Physics and Astronomy", "note": "\u00a9 The Author(s), under exclusive licence to Springer Nature Limited 2023.
\n\nWe thank L. Balents, M. Ye, R. D. Averitt, P. A. Lee, M. Mitrano, M. Buzzi, S. K. Cushing, P. Prelov\u0161ek, D. Gole\u017e and V. Galitski for useful discussions. We thank S. J. Moon for sharing his equilibrium optical conductivity results. This work is supported by ARO MURI grant no. W911NF-16-1-0361. D.H. acknowledges support for instrumentation from the David and Lucile Packard Foundation and from the Institute for Quantum Information and Matter (IQIM), an NSF Physics Frontiers Center (PHY-1733907). S.D.W. acknowledges partial support via NSF award DMR-1729489. X.L. acknowledges support from the Caltech Postdoctoral Prize Fellowship and IQIM. M.B. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy Cluster of Excellence Matter and Light for Quantum Computing (ML4Q) EXC 2004/1-390534769. Z.L. was funded by the Gordon and Betty Moore Foundation's EPiQS initiative, grant no. GBMF4545, and J1-2463 project and P1-0044 program of the Slovenian Research Agency.
\n\nThese authors contributed equally: Omar Mehio, Xinwei Li, Honglie Ning.
O.M. and D.H. conceived the experiment. O.M. constructed the time-resolved time-domain THz spectrometer with contributions from X.L. and N.J.L. O.M., X.L., H.N. and Y.H. collected and analysed the data. Z.L. performed the exact diagonalization calculations and interpreted the results with O.M. and M.B. Z.P. and S.W. synthesized and characterized the sample. O.M. and D.H. wrote the paper with input from all authors.
\n\nSource data are provided with this paper. All other data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request.
\n\nThe authors declare no competing interests.
", "abstract": "The undoped antiferromagnetic Mott insulator naturally has one charge carrier per lattice site. When it is doped with additional carriers, they are unstable to spin-fluctuation-mediated Cooper pairing as well as other unconventional types of charge, spin and orbital current ordering. Photo-excitation can produce charge carriers in the form of empty (holons) and doubly occupied (doublons) sites that may also exhibit charge instabilities. There is evidence that antiferromagnetic correlations enhance attractive interactions between holons and doublons, which can then form bound pairs known as Hubbard excitons, and that these might self-organize into an insulating Hubbard exciton fluid. However, this out-of-equilibrium phenomenon has not been experimentally detected. Here we report the transient formation of a Hubbard exciton fluid in the antiferromagnetic Mott insulator Sr\u2082IrO\u2084 using ultrafast terahertz conductivity. Following photo-excitation, we observe rapid spectral-weight transfer from a Drude metallic response to an insulating response. The latter is characterized by a finite-energy peak originating from intraexcitonic transitions, whose assignment is corroborated by our numerical simulations of an extended Hubbard model. The lifetime of the peak is short (approximately one picosecond) and scales exponentially with the Mott gap size, implying extremely strong coupling to magnon modes.
", "date": "2023-09-14", "date_type": "published", "publication": "Nature Physics", "publisher": "Nature Publishing Group", "issn": "1745-2473", "official_url": "https://authors.library.caltech.edu/records/f2wj0-p4753", "funders": { "items": [ { "grant_number": "W911NF-16-1-0361" }, {}, { "grant_number": "PHY-1733907" }, { "grant_number": "DMR-1729489" }, { "grant_number": "(ML4Q) EXC 2004/1 390534769" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF4545" }, { "agency": "Javna Agencija za Raziskovalno Dejavnost RS", "grant_number": "J1- 2463" }, { "agency": "Javna Agencija za Raziskovalno Dejavnost RS", "grant_number": "P1-0044" } ] }, "local_group": { "items": [ { "id": "IQIM" } ] }, "doi": "10.1038/s41567-023-02204-2", "primary_object": { "basename": "41567_2023_2204_Fig7_ESM.jpg", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_Fig7_ESM.jpg" }, "related_objects": [ { "basename": "41567_2023_2204_MOESM3_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_MOESM3_ESM.xlsx" }, { "basename": "41567_2023_2204_MOESM9_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_MOESM9_ESM.xlsx" }, { "basename": "41567_2023_2204_MOESM2_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_MOESM2_ESM.xlsx" }, { "basename": "41567_2023_2204_MOESM4_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_MOESM4_ESM.xlsx" }, { "basename": "41567_2023_2204_MOESM7_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_MOESM7_ESM.xlsx" }, { "basename": "41567_2023_2204_Fig6_ESM.jpg", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_Fig6_ESM.jpg" }, { "basename": "41567_2023_2204_MOESM6_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_MOESM6_ESM.xlsx" }, { "basename": "41567_2023_2204_MOESM5_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_MOESM5_ESM.xlsx" }, { "basename": "41567_2023_2204_MOESM8_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_MOESM8_ESM.xlsx" }, { "basename": "41567_2023_2204_Fig5_ESM.jpg", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_Fig5_ESM.jpg" }, { "basename": "41567_2023_2204_Fig8_ESM.jpg", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_Fig8_ESM.jpg" }, { "basename": "41567_2023_2204_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/f2wj0-p4753/files/41567_2023_2204_MOESM1_ESM.pdf" } ], "resource_type": "article", "pub_year": "2023", "author_list": "Mehio, Omar; Li, Xinwei; et el." } ]