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Title: Ultralow thermal conductivity in disordered, layered WSe{sub 2} crystals.

Abstract

The cross-plane thermal conductivity of thin films of WSe{sub 2} grown from alternating W and Se layers is as small as 0.05 watts per meter per degree kelvin at room temperature, 30 times smaller than the c-axis thermal conductivity of single-crystal WSe{sub 2} and a factor of 6 smaller than the predicted minimum thermal conductivity for this material. We attribute the ultralow thermal conductivity of these disordered, layered crystals to the localization of lattice vibrations induced by the random stacking of two-dimensional crystalline WSe{sub 2} sheets. Disordering of the layered structure by ion bombardment increases the thermal conductivity.

Authors:
; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
OSTI Identifier:
946675
Report Number(s):
ANL/XSD/JA-57823
TRN: US200903%%455
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Scienceexpress; Journal Volume: 315; Journal Issue: 5810 ; Jan. 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
36 MATERIALS SCIENCE; LATTICE VIBRATIONS; THERMAL CONDUCTIVITY; THIN FILMS; TUNGSTEN ALLOYS; SELENIUM ALLOYS; ORDER PARAMETERS

Citation Formats

Chiritescu, C., Cahill, D. G., Nguyen, N., Johnson, D., Bodapati, A., Keblinski, P., Zschack, P., X-Ray Science Division, Univ. of Illinois, Univ. of Oregon, and Rensselaer Polytechnic. Ultralow thermal conductivity in disordered, layered WSe{sub 2} crystals.. United States: N. p., 2007. Web. doi:10.1126/science.1136494.
Chiritescu, C., Cahill, D. G., Nguyen, N., Johnson, D., Bodapati, A., Keblinski, P., Zschack, P., X-Ray Science Division, Univ. of Illinois, Univ. of Oregon, & Rensselaer Polytechnic. Ultralow thermal conductivity in disordered, layered WSe{sub 2} crystals.. United States. doi:10.1126/science.1136494.
Chiritescu, C., Cahill, D. G., Nguyen, N., Johnson, D., Bodapati, A., Keblinski, P., Zschack, P., X-Ray Science Division, Univ. of Illinois, Univ. of Oregon, and Rensselaer Polytechnic. Mon . "Ultralow thermal conductivity in disordered, layered WSe{sub 2} crystals.". United States. doi:10.1126/science.1136494.
@article{osti_946675,
title = {Ultralow thermal conductivity in disordered, layered WSe{sub 2} crystals.},
author = {Chiritescu, C. and Cahill, D. G. and Nguyen, N. and Johnson, D. and Bodapati, A. and Keblinski, P. and Zschack, P. and X-Ray Science Division and Univ. of Illinois and Univ. of Oregon and Rensselaer Polytechnic},
abstractNote = {The cross-plane thermal conductivity of thin films of WSe{sub 2} grown from alternating W and Se layers is as small as 0.05 watts per meter per degree kelvin at room temperature, 30 times smaller than the c-axis thermal conductivity of single-crystal WSe{sub 2} and a factor of 6 smaller than the predicted minimum thermal conductivity for this material. We attribute the ultralow thermal conductivity of these disordered, layered crystals to the localization of lattice vibrations induced by the random stacking of two-dimensional crystalline WSe{sub 2} sheets. Disordering of the layered structure by ion bombardment increases the thermal conductivity.},
doi = {10.1126/science.1136494},
journal = {Scienceexpress},
number = 5810 ; Jan. 2007,
volume = 315,
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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