Atomistic simulations of thermal transport in Si and SiGe based materials: From bulk to nanostructures

ORAL

Abstract

It has been recently proposed that Si and SiGe based nanostructured materials may exhibit low thermal conductivity and overall promising properties for thermoelectric applications. Hence there is a considerable interest in developing accurate theoretical and computational methods which can help interpret recent measurements, identify the physical origin of the reduced thermal conductivity, as well as shed light on the interplay between disorder and nanostructuring in determining a high figure of merit. In this work, we investigate the capability of an atomistic Green's function method [1] to describe phonon transport in several types of Si and SiGe based systems: amorphous Si, SiGe alloys, planar and nanodot Si/SiGe multilayers. We compare our results with experimental data [2,3], and with the findings of molecular dynamics simulations and calculations based on the Boltzmann transport equation. [1] I. Savic, N. Mingo, and D. A. Stewart, Phys. Rev. Lett. 101, 165502 (2008). [2] S.-M. Lee, D. G. Cahill, and R. Venkatasubramanian, Appl. Phys. Lett. 70, 2957 (1997). [3] G. Pernot et al., submitted.

–

Authors

  • Ivana Savic

    Department of Chemistry, UC Davis, USA

  • N. Mingo

    CEA Grenoble and UC Santa Cruz, CEA, France, LITEN, CEA-Grenoble, France, CEA-Grenoble

  • Davide Donadio

    Dept. Chemistry, UC Davis, Dept. of Chemistry, UC Davis, Department of Chemistry, UC Davis, USA

  • Giulia Galli

    Dept. of Chemistry and Dept. of Physics, UC Davis, Department of Chemistry and Department of Physics, University of California Davis, Dept of Chemistry \& Dept Physics, UC Davis, Department of Chemistry and Department of Physics, UC Davis, USA, Department of Chemistry and Department of Physics, University of California, Davis, UC Davis, Department of Chemistry, University of California, Davis, USA, University of California, Davis, Department of Chemistry and Department of Physics, University of California, Davis, CA, 95616, Department of Chemistry and Department of Physics, University of California, Davis, CA 95616, Chemistry Department and Physics Department UC Davis, Davis CA