APS March Meeting 2012
Volume 57, Number 1
Monday–Friday, February 27–March 2 2012;
Boston, Massachusetts
Session X10: Invited Session: Thermal Properties and Electron-Phonon Coupling from First Principles
2:30 PM–5:30 PM,
Thursday, March 1, 2012
Room: 210A
Sponsoring
Unit:
DCOMP
Chair: Anderson Janotti, University of California, Santa Barbara
Abstract ID: BAPS.2012.MAR.X10.5
Abstract: X10.00005 : Large scale atomistic approaches to thermal transport and phonon scattering in nanostructured materials*
4:54 PM–5:30 PM
Preview Abstract
Abstract
Author:
Ivana Savic
(Department of Chemistry, University of California at Davis, Davis, California, USA)
Decreasing the thermal conductivity of bulk materials by nanostructuring
and dimensionality reduction, or by introducing some amount of disorder
represents a promising strategy in the search for efficient
thermoelectric materials [1]. For example, considerable improvements of
the thermoelectric efficiency in nanowires with surface roughness [2],
superlattices [3] and nanocomposites [4] have been attributed to a
significantly reduced thermal conductivity. In order to accurately
describe thermal transport processes in complex nanostructured
materials and directly compare with experiments, the development of
theoretical and computational approaches that can account for both
anharmonic and disorder effects in large samples is highly desirable. We
will first summarize the strengths and weaknesses of the standard
atomistic approaches to thermal transport (molecular dynamics [5],
Boltzmann transport equation [6] and Green's function approach [7]) . We
will then focus on the methods based on the solution of the Boltzmann
transport equation, that are computationally too demanding, at present,
to treat large scale systems and thus to investigate realistic
materials. We will present a Monte Carlo method [8] to solve the
Boltzmann transport equation in the relaxation time approximation [9],
that enables computation of the thermal conductivity of ordered and
disordered systems with a number of atoms up to an order of magnitude
larger than feasible with straightforward integration. We will present a
comparison between exact and Monte Carlo Boltzmann transport results for
small SiGe nanostructures and then use the Monte Carlo method to analyze
the thermal properties of realistic SiGe nanostructured materials. This
work is done in collaboration with Davide Donadio, Francois Gygi, and
Giulia Galli from UC Davis.\\[4pt]
[1] See e.g. A. J. Minnich, M. S. Dresselhaus, Z. F. Ren, and G. Chen,
Energy Environ. Sci. 2, 466 (2009).\\[0pt]
[2] A. I. Hochbaum et al, Nature 451, 163 (2008).\\[0pt]
[3] R. Venkatasubramanian, E. Siivola, T. Colpitts, and B. O'Quinn,
Nature 413, 597 (2001).\\[0pt]
[4] B. Poudel et al, Science 320, 634 (2008).\\[0pt]
[5] See e.g. Y. He, D. Donadio, and G. Galli, Nano Lett. 11, 3608 (2011).\\[0pt]
[6] See e.g. A. Ward and D. A. Broido, Phys. Rev. B 81, 085205 (2010).\\[0pt]
[7] See e.g. I. Savic, N. Mingo, and D. A. Stewart, Phys. Rev. Lett.
101, 165502 (2008).\\[0pt]
[8] I. Savic, D.Donadio, F.Gygi, and G.Galli (in preparation).\\[0pt]
[9] See e.g. J. E. Turney, E. S. Landry, A. J. H. McGaughey, and C. H.
Amon, Phys. Rev. B, 79, 064301 (2009).
*Work supported by DOE-SciDAC-e, DE-FC02-06ER25777.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2012.MAR.X10.5