Signatures of Higher Order Topology in S-Bi-S Junctions

ORAL

Abstract

Perfect 3D pure bismuth is a very intriguing material, but its electronic states were considered topologically trivial until recent works suggesting that it may host 1D helical states on some hinges. Indeed, bismuth fits in the new class of material called "second order topological insulator" (SOTI).

Our group participated in the discovery of this first SOTI [1] by controling the phase bias on a single-crystalline bismuth nanowires coupled to superconducting contacts. We demonstrated that supercurrent is carried by narrow ballistic channels, both in low frequency [2] and high frequency experiments [3].

In this talk, I will present ongoing works on ring-shaped bismuth samples probed with low frequency superconducting switching statistics analysis. This upgraded method provides additionnal informations on the supercurrent-carrying states, and tackles perfect Andreev levels crossing resolution and parity lifetime.

[1] F. Schindler et al., Nat. Phys. 9, 918-924 (2018).
[2] A. Murani et al., Nat. Comm. 8, 15941 (2017).
[3] A. Murani et al., Phys. Rev. Lett. 122, 076802 (2019).

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Presenters

  • Alexandre Bernard

    • Laboratoire de Physique des Solides, Université Paris-Saclay, CNRS, UMR 8502, Orsay, France

Authors

  • Alexandre Bernard

    • Laboratoire de Physique des Solides, Université Paris-Saclay, CNRS, UMR 8502, Orsay, France

  • Alik Kasumov

    • Laboratoire de Physique des Solides, Université Paris-Saclay, CNRS, UMR 8502, Orsay, France

  • Richard Deblock

    • Laboratoire de Physique des Solides, Université Paris-Saclay, CNRS, UMR 8502, Orsay, France
    • Universite Paris-Saclay

  • Yang Peng

    • Department of Physics and Astronomy, California State University, Northridge, USA
    • Caltech
    • California State University, Northridge

  • Yuval Oreg

    • Weizmann Institute of Science
    • Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel
    • Department of Condensed Matter Physics, Weizmann Institute of Science

  • Felix von Oppen

    • Freie Universitat Berlin
    • Dahlem Center for Complex Quantum Systems and Fachbereich Physik, Freie Universität Berlin, Berlin, Germany

  • Helene Bouchiat

    • Laboratoire de Physique des Solides, Université Paris-Saclay, CNRS, UMR 8502, Orsay, France
    • Universite Paris-Saclay

  • Sophie Gueron

    • Laboratoire de Physique des Solides, Université Paris-Saclay, CNRS, UMR 8502, Orsay, France
    • Universite Paris-Saclay