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Title: Interaction of Lamb modes with two-level systems in amorphous nanoscopic membranes.

Abstract

Using a generalized model of interaction between a two-level system (TLS) and an arbitrary deformation of the material, we calculate the interaction of Lamb modes with TLSs in amorphous nanoscopic membranes. We compare the mean free paths of the Lamb modes of different symmetries and calculate the heat conductivity {kappa}. In the limit of an infinitely wide membrane, the heat conductivity is divergent. Nevertheless, the finite size of the membrane imposes a lower cutoff for the phonon frequencies, which leads to the temperature dependence {kappa}{alpha}T(a+b ln T). This temperature dependence is a hallmark of the TLS-limited heat conductance at low temperature.

Authors:
; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC); NATO; Academy of Finland
OSTI Identifier:
970374
Report Number(s):
ANL/MSD/JA-60529
Journal ID: ISSN 1098-0121; TRN: US1000744
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Phys. Rev. B; Journal Volume: 76; Journal Issue: 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; DEFORMATION; MEAN FREE PATH; MEMBRANES; PHONONS; TEMPERATURE DEPENDENCE

Citation Formats

Kuhn, T., Anghel, D. V., Galperin, Y. M., Manninen, M., Materials Science Division, Univ. Jyvaskyla, National Inst. for Physics and Nuclear Engineering, Bogolivbov Lab. Theoretical Physics, Univ. Oslo, and Russian Academy of Sciences. Interaction of Lamb modes with two-level systems in amorphous nanoscopic membranes.. United States: N. p., 2007. Web. doi:10.1103/PhysRevB.76.165425.
Kuhn, T., Anghel, D. V., Galperin, Y. M., Manninen, M., Materials Science Division, Univ. Jyvaskyla, National Inst. for Physics and Nuclear Engineering, Bogolivbov Lab. Theoretical Physics, Univ. Oslo, & Russian Academy of Sciences. Interaction of Lamb modes with two-level systems in amorphous nanoscopic membranes.. United States. doi:10.1103/PhysRevB.76.165425.
Kuhn, T., Anghel, D. V., Galperin, Y. M., Manninen, M., Materials Science Division, Univ. Jyvaskyla, National Inst. for Physics and Nuclear Engineering, Bogolivbov Lab. Theoretical Physics, Univ. Oslo, and Russian Academy of Sciences. Mon . "Interaction of Lamb modes with two-level systems in amorphous nanoscopic membranes.". United States. doi:10.1103/PhysRevB.76.165425.
@article{osti_970374,
title = {Interaction of Lamb modes with two-level systems in amorphous nanoscopic membranes.},
author = {Kuhn, T. and Anghel, D. V. and Galperin, Y. M. and Manninen, M. and Materials Science Division and Univ. Jyvaskyla and National Inst. for Physics and Nuclear Engineering and Bogolivbov Lab. Theoretical Physics and Univ. Oslo and Russian Academy of Sciences},
abstractNote = {Using a generalized model of interaction between a two-level system (TLS) and an arbitrary deformation of the material, we calculate the interaction of Lamb modes with TLSs in amorphous nanoscopic membranes. We compare the mean free paths of the Lamb modes of different symmetries and calculate the heat conductivity {kappa}. In the limit of an infinitely wide membrane, the heat conductivity is divergent. Nevertheless, the finite size of the membrane imposes a lower cutoff for the phonon frequencies, which leads to the temperature dependence {kappa}{alpha}T(a+b ln T). This temperature dependence is a hallmark of the TLS-limited heat conductance at low temperature.},
doi = {10.1103/PhysRevB.76.165425},
journal = {Phys. Rev. B},
number = 2007,
volume = 76,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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