Topological-Metal to Band-Insulator Transition in (Bi$_{1-x}$In$_x)_2$Se$_3$ Thin Films

ORAL

Abstract

By combining transport and photoemission measurements on (Bi$_{1-x}$In$_x)_2$Se$_3$ thin films, we report that this system transforms from a topologically nontrivial metal into a topologically trivial band insulator through three quantum phase transitions. At $x\approx $3{\%}--7{\%}, there is a transition from a topologically nontrivial metal to a trivial metal. At $x\approx $15{\%}, the metal becomes a variable-range-hopping insulator. Finally, above $x\approx $25{\%}, the system becomes a true band insulator with its resistance immeasurably large even at room temperature. This material provides a new venue to investigate topologically tunable physics and devices with seamless gating or tunneling insulators.

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Authors

  • Matthew Brahlek

    • Rutgers University
    • Rutgers, the State University of New Jersey
    • Rutgers University Physics and Astronomy Department

  • Namrata Bansal

    • Rutgers University Physics and Astronomy Department

  • Nikesh Koirala

    • Rutgers University Physics and Astronomy Department

  • Su-Yang Xu

    • Princeton University Physics Department

  • Madhab Neupane

    • Princeton University Physics Department

  • Chang Liu

    • Princeton University Physics Department

  • M. Z. Hasan

    • Princeton University Physics Department
    • Princeton University

  • Seongshik Oh

    • Rutgers University
    • Rutgers, the State University of New Jersey
    • Rutgers University Physics and Astronomy Department