Neutron Scattering Study of the Temperature-Dependent Phonon Spectra of AgSbTe$_{2}$

ORAL

Abstract

The thermoelectric material AgSbTe$_{2}$ has attracted much attention due to its simple rocksalt structure, high thermoelectric figure-of-merit, and its extremely low thermal conductivity in bulk samples. Previous theoretical studies have suggested that phonons can be scattered by anharmonicity (phonon-phonon coupling) and nano-defects in AgSbTe$_{2}$. However, systematic measurements of phonons in this compound have not been available. We report our results of detailed time-of-flight neutron scattering measurements, as a function of temperature, and departure from stoichiometry. The temperature dependence of the phonon density-of-states is discussed, and compared with the reported thermal conductivity in this system.

*O.D. and J.M. acknowledge funding from US DOE, Office of Basic Energy Sciences as part of the S3TEC Energy Frontier Research Center, DOE DE-SC0001299.

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Authors

  • Jie Ma

    • Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA

  • Olivier Delaire

    • Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA

  • Andrew May

    • Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA

  • Michael McGuire

    • Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA

  • Brian Sales

    • Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA

  • Olivier Gourdon

    • Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA

  • Ashfia Huq

    • Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA

  • Douglas Abernathy

    • Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA

  • Matthew Stone

    • Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA