Effects of the topological phase transition and band inversion on ultrafast dynamics in topological crystalline insulators

ORAL

Abstract

Topological crystalline insulators, characterized by a gapless metallic state on their high-symmetry surfaces that is protected by crystalline symmetry, are realized both theoretically and experimentally in the Pb$_{1-x}$Sn$_{x}$Te and Pb$_{1-x}$Sn$_{x}$Se compounds. In these materials, a topological phase transition and band inversion can be induced by doping, pressure or temperature. We use femtosecond optical pump-probe spectroscopy to study the evolution of the ultrafast dynamics as a function of both temperature and doping in the Pb$_{1-x}$Sn$_{x}$Te system. The influence of these parameters on the topological phase transition and band inversion, as well as on quasiparticle dynamics, will be discussed.

*Supported by LANL LDRD and LANL-UCRP programs.

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Authors

  • Y.M. Dai

    • Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545

  • J. Bowlan

    • Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545

  • A.J. Taylor

    • Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545

  • D.A. Yarotski

    • Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545

  • R.P. Prasankumar

    • Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM 87545

  • R.D. Zhong

    • Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973

  • G.D. Gu

    • Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973

  • T. Valla

    • Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973

  • C.C. Homes

    • Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973

  • T. Yilmaz

    • Department of Physics, University of Connecticut, Storrs, Connecticut 06269

  • B. Sinkovic

    • Department of Physics, University of Connecticut, Storrs, Connecticut 06269