Nanoscale imaging of equilibrium quantum Hall edge currents in graphene

ORAL  · Invited

Abstract

The quantum Hall effect has served as a model system to understand topology in condensed matter physics. Although edge states play an important role in explaining the quantization of the Hall conductance, the actual edge currents have evaded direct measurement. Using a scanning nano SQUID-on-tip, we image the equilibrium currents of individual quantum Hall edge states in monolayer graphene. We reveal that the edge states, which are commonly assumed to carry only a chiral downstream current, in fact, carry a pair of counterpropagating currents, in which the topological downstream current in the incompressible region is counterbalanced by a non-topological upstream current flowing in the adjacent compressible region.

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Publication: Nanoscale imaging of equilibrium quantum Hall edge currents and of the magnetic monopole response in graphene
Nature Physics volume 16, pages164–170 (2020)
https://doi.org/10.1038/s41567-019-0713-3

Presenters

  • Aviram Uri

    • MIT

Authors

  • Aviram Uri

    • MIT

  • Youngwook Kim

    • Max Planck Institute for Solid State Physics

  • Kousik Bagani

    • Weizmann Institute of Science

  • Cyprian K Lewandowski

    • Florida State University

  • Sameer Grover

    • Weizmann Institute of Science

  • Nadav Auerbach

    • Weizmann Institute of Science

  • Ella O Lachman

    • University of California, Berkeley

  • Yuri Myasoedov

    • Weizmann Institute of Science

  • Takashi Taniguchi

    • National Institute for Materials Science
    • Kyoto Univ
    • International Center for Materials Nanoarchitectonics, National Institute of Materials Science
    • Kyoto University
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-044, Japan
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • National Institute for Materials Science, Japan
    • National Institute For Materials Science
    • NIMS
    • National Institute for Material Science
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan
    • NIMS Japan

  • Kenji Watanabe

    • National Institute for Materials Science
    • Research Center for Functional Materials, National Institute of Materials Science
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-044, Japan
    • NIMS
    • Research Center for Functional Materials, National Institute for Materials Science
    • National Institute for Materials Science, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Japan
    • NIMS Japan

  • Jurgen H Smet

    • Max Planck Institute for Solid State Physics

  • Eli Zeldov

    • Weizmann Institute of Science