CaltechAUTHORS: Article
https://feeds.library.caltech.edu/people/Dykman-M-I/article.rss
A Caltech Library Repository Feedhttp://www.rssboard.org/rss-specificationpython-feedgenenFri, 09 Aug 2024 18:55:25 -0700Detecting and characterizing frequency fluctuations of vibrational modes
https://resolver.caltech.edu/CaltechAUTHORS:20111031-094919664
Year: 2011
DOI: 10.1103/PhysRevB.84.144301
We show how frequency fluctuations of a vibrational mode can be separated from other sources of phase noise.
The method is based on the analysis of the time dependence of the complex amplitude of forced vibrations. The
moments of the complex amplitude sensitively depend on the frequency noise statistics and its power spectrum.
The analysis applies to classical and to quantum vibrations.https://resolver.caltech.edu/CaltechAUTHORS:20111031-094919664Nonlinear damping and dephasing in nanomechanical systems
https://resolver.caltech.edu/CaltechAUTHORS:20161129-110301068
Year: 2016
DOI: 10.1103/PhysRevB.94.195440
We present a microscopic theory of nonlinear damping and dephasing of low-frequency eigenmodes in nanomechanical and micromechanical systems. The mechanism of the both effects is scattering of thermally excited vibrational modes off the considered eigenmode. The scattering is accompanied by energy transfer of 2ℏω_0 for nonlinear damping and is quasielastic for dephasing. We develop a formalism that allows studying both spatially uniform systems and systems with a strong nonuniformity, which is smooth on the typical wavelength of thermal modes but is pronounced on their mean free path. The formalism accounts for the decay of thermal modes, which plays a major role in the nonlinear damping and dephasing. We identify the nonlinear analogs of the Landau-Rumer, thermoelastic, and Akhiezer mechanisms and find the dependence of the relaxation parameters on the temperature and the geometry of a system.https://resolver.caltech.edu/CaltechAUTHORS:20161129-110301068Resonantly Induced Friction and Frequency Combs in Driven Nanomechanical Systems
https://resolver.caltech.edu/CaltechAUTHORS:20190627-094320647
Year: 2019
DOI: 10.1103/physrevlett.122.254301
We propose a new mechanism of friction in resonantly driven vibrational systems. The form of the friction force follows from the time- and spatial-symmetry arguments. We consider a microscopic mechanism of this resonant force in nanomechanical systems. The friction can be negative, leading to the onset of self-sustained oscillations of the amplitude and phase of forced vibrations, which result in a frequency comb in the power spectrum.https://resolver.caltech.edu/CaltechAUTHORS:20190627-094320647