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Title: Thermal Conductivity of GaN Nanotubes Simulated by Nonequilibrium Molecular Dynamics

Abstract

Thermal conductivity of GaN nanotubes along the tube axis is investigated over the temperature range of 600K-2300K using homogeneous nonequilibrium molecular dynamics. In general, the thermal conductivity of nanotubes is smaller than that for the bulk GaN single crystal. The thermal conductivity is also found to decrease with temperature and increase with increasing wall thickness of the nanotubes. The change of phonon spectrum and surface inelastic scattering may account for the reduction of thermal conductivity in the nanotubes, while thermal softening and high frequency phonon interactions at high temperatures may provide an explanation for its decrease with increasing temperature.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
908732
Report Number(s):
PNNL-SA-53240
Journal ID: ISSN 0163-1829; PRBMDO; 8208; KC0201020; TRN: US0703754
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter, 75(12):Art. No. 153303; Journal Volume: 75; Journal Issue: 12
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; INELASTIC SCATTERING; MONOCRYSTALS; NANOTUBES; PHONONS; THERMAL CONDUCTIVITY; THICKNESS; Thermal Conductivity; GaN Nanotubes; computer simulation; Environmental Molecular Sciences Laboratory

Citation Formats

Wang, Zhiguo, Gao, Fei, Crocombette, J.-P., Zu, Xiaotao, Yang, Li, and Weber, William J. Thermal Conductivity of GaN Nanotubes Simulated by Nonequilibrium Molecular Dynamics. United States: N. p., 2007. Web. doi:10.1103/PhysRevB.75.153303.
Wang, Zhiguo, Gao, Fei, Crocombette, J.-P., Zu, Xiaotao, Yang, Li, & Weber, William J. Thermal Conductivity of GaN Nanotubes Simulated by Nonequilibrium Molecular Dynamics. United States. doi:10.1103/PhysRevB.75.153303.
Wang, Zhiguo, Gao, Fei, Crocombette, J.-P., Zu, Xiaotao, Yang, Li, and Weber, William J. Sun . "Thermal Conductivity of GaN Nanotubes Simulated by Nonequilibrium Molecular Dynamics". United States. doi:10.1103/PhysRevB.75.153303.
@article{osti_908732,
title = {Thermal Conductivity of GaN Nanotubes Simulated by Nonequilibrium Molecular Dynamics},
author = {Wang, Zhiguo and Gao, Fei and Crocombette, J.-P. and Zu, Xiaotao and Yang, Li and Weber, William J.},
abstractNote = {Thermal conductivity of GaN nanotubes along the tube axis is investigated over the temperature range of 600K-2300K using homogeneous nonequilibrium molecular dynamics. In general, the thermal conductivity of nanotubes is smaller than that for the bulk GaN single crystal. The thermal conductivity is also found to decrease with temperature and increase with increasing wall thickness of the nanotubes. The change of phonon spectrum and surface inelastic scattering may account for the reduction of thermal conductivity in the nanotubes, while thermal softening and high frequency phonon interactions at high temperatures may provide an explanation for its decrease with increasing temperature.},
doi = {10.1103/PhysRevB.75.153303},
journal = {Physical Review. B, Condensed Matter, 75(12):Art. No. 153303},
number = 12,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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  • Abstract not provided.
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