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Dynamic disorder in BaTiS<sub>3 </sub>

ORAL

Abstract

BaTiS3 exhibits a hexagonal perovskite structure comprised of columns of sulphur coordinated Ti linked by barium making it a quasi-1D structure. Neutron pair distribution function measurements reveal that the Ti atomic displacement parameters increase with decreasing temperature. This observation suggest proximity to a ferroelectric type phase transition or, alternatively, dynamic disorder persisting in the ground state. A combination of phonon spectroscopy by inelastic x-ray scattering and inelastic neutron scattering supports the dynamic disorder scenario which extends into the quantum regime with Ti occupying a double-well potential. This unique dynamics have a profound consequence on the thermal conductivity and suggest a novel mechanism for thermal transport design.

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Presenters

  • Raphael Hermann

    Oak Ridge National Laboratory, Oak Ridge National Lab

Authors

  • Raphael Hermann

    Oak Ridge National Laboratory, Oak Ridge National Lab

  • Michael E Manley

    Oak Ridge National Laboratory

  • Barry Winn

    Oak Ridge National Laboratory

  • Katharine L. Page

    The University of Tennessee, Neutron Scattering Division & Materials Science and Engineering Department, Oak Ridge National Laboratory, Oak Ridge, TN & University of Tennessee, Knoxville, TN

  • Ahmet Alatas

    Argonne National Laboratory, APS, Argonne National Laboratory, Advanced Photon Source, Argonne National Laboratory

  • Jaeyun Moon

    California Institute of Technology

  • Austin Minnich

    Division of Engineering and Applied Science, California Institute of Technology, California Institute of Technology, Caltech, Division of Engineering and Applied Sciences, California Institute of Technology

  • Jayakanth Ravichandran

    University of Southern California, Los Angeles, University of Southern California