Phonon Dispersions of Thermoelectric SnSe

ORAL

Abstract

SnSe has recently attracted significant interest as a thermoelectric material with very high $zT>2$ along two crystallographic axes. A favorable property of SnSe is its very low thermal conductivity, which is below $1Wm^{-1}K^{-1}$ along all axes even at ambient temperature, and decreases with temperature. However, the degree of anisotropy of the thermal conductivity remains somewhat controversial. We present our results of detailed inelastic neutron scattering measurements of the phonon dispersions and their temperature dependence. The results are compared with first-principles calculations to investigate the origin of the low thermal conductivity and its anisotropy.

*Funding from the DOE, BES, MSED and as part of the S3TEC EFRC. OD acknowledges the Office of Science Early Career Research Program.

Authors

  • Chen Li

    • Materials Science and Technology Division, Oak Ridge National Laboratory
    • Oak Ridge National Laboratory
  • Jiawang Hong

    • Oak Ridge National Laboratory
  • Andrew May

    • Oak Ridge National Laboratory
  • J. Ma

    • Quantum Condensed Matter Division, ORNL
    • Oak Ridge National Laboratory
    • Quantum Condensed Matter Division, Oak Ridge National Laboratory
    • Oak Ridge Natl Lab, TN, USA
  • Tao Hong

    • Quantum Condensed Matter Division, ORNL
    • Oak Ridge National Laboratory
  • Songxue Chi

    • Oak Ridge National Laboratory
  • Georg Ehlers

    • Neutron Scattering Science Division, ORNL, Oak Ridge, USA
    • Oak Ridge National Laboratory
    • Oak Ridge National Laboratory, TN
  • Olivier Delaire

    • Oak Ridge National Laboratory