Effect of surface roughness on phonon thermal conductance in the quantum limit

We study the effect on the thermal conductance of phonon scattering by surface roughness using a simple scalar model and a full elasticity calculation. The scattering at low frequencies in the elasticity calculation shows quite different power law dependences from the 1D Rayleigh scattering predicte...

Full description

Saved in:
Bibliographic Details
Published in:Physica. B, Condensed matter Condensed matter, 2002-05, Vol.316, p.389-392
Main Authors: Santamore, D.H., Cross, M.C.
Format: Article
Language:English
Subjects:
Elasticity
Quantised thermal conductance
Surface scattering
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We study the effect on the thermal conductance of phonon scattering by surface roughness using a simple scalar model and a full elasticity calculation. The scattering at low frequencies in the elasticity calculation shows quite different power law dependences from the 1D Rayleigh scattering predicted by the scalar model, due to the peculiar dispersion relation of the elastic modes. The scattering analysis is used to explain the unexpected decrease in the thermal conductance below universal level reported by Schwab et al. (Nature 404 (2000) 974). Our results suggest that the surface roughness is an important factor in the reduction of the thermal conductance in low temperature.
ISSN:0921-4526
1873-2135
DOI:10.1016/S0921-4526(02)00522-7