Analysis of thermal conductance of ballistic point contacts

Changwook Jeong, Birck Nanotechnology Center, Purdue University
Mark S. Lundstrom, Birck Nanotechnology Center, Purdue University

Date of this Version



Changwook Jeong and Mark Lundstrom, Appl. Phys. Lett. 100, 233109 (2012);


Copyright (2012) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Appl. Phys. Lett. 100, 233109 (2012) and may be found at The following article has been submitted to/accepted by Applied Physics Letters. Copyright (2012) Changwook Jeong and Mark Lundstrom. This article is distributed under a Creative Commons Attribution 3.0 Unported License.


Substantial reduction of thermal conductance (K-ph) was recently reported for air gap heterostructures (AGHs) in which two bulk layers were connected by low-density nanopillars. We analyze K-ph using a full phonon dispersion and including important phonon scattering. We find a transition from ballistic at low temperatures to quasi-ballistic transport near room temperature and explain the slow roll-off in K-ph that occurs near room temperature. We show that the density of nanopillars deduced from the analysis depends strongly on the phonon dispersion assumed. Our model provides a good agreement with experiment that will be necessary to design AGHs for thermoelectric applications. (C) 2012 American Institute of Physics. []


Nanoscience and Nanotechnology