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Imaging quantum Hall edge state: part II

ORAL

Abstract

Topologically protected edge states that conduct ballistic transport in a two-dimensional electron gas under strong out-of-plane magnetic field provides a natural explanation for the quantum Hall effect. In the zeroth Landau level of monolayer graphene, strong Coulomb interaction drives spontaneous breaking of spin and valley symmetries, giving rise to rich physics in the quantum Hall edge states. However, local measurements with the ability to image edge states in real space and probe their symmetry breaking patterns are limited due to sample disorder and limited resolution of the probe. Here we present results of scanning tunneling microscopy/spectroscopy measurements on an ultra-clean graphene sample with a gate-defined lateral interface. In this second talk in a series of three presentations, I will show the emergence of symmetry-breaking edge states tuned by gate induced potential which exhibits unexpected spatial configurations. I will show how these configurations can be understood by the energetic competition between edge electrostatic potential and interactions. These results transcend the conventional picture of edge reconstruction and highlight the role of interaction effects on edge state physics.

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Presenters

  • Haotan Han

    Princeton University

Authors

  • Haotan Han

    Princeton University

  • Jiachen Yu

    Princeton University

  • Kristina G Wolinski

    Princeton University

  • Ruihua Fan

    University of California, Berkeley

  • Tianle Wang

    University of California, Berkeley

  • Amir Shapour Mohammadi

    University of California, Berkeley, Princeton University

  • Liam A Cohen

    University of California, Santa Barbara

  • Kenji Watanabe

    National Institute for Materials Science, NIMS, Research Center for Functional Materials, National Institute for Materials Science, Research Center for Electronic and Optical Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, Research Center for Functional Materials, National Institute of Material Science, Tsukuba, Japan, National Institute of Materials Science, Advanced Materials Laboratory, National Institute for Materials Science

  • Takashi Taniguchi

    National Institute for Materials Science, International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, International Center for Materials Nanoarchitectonics, National Institute of Material Science, Tsukuba, Japan, Advanced Materials Laboratory, National Institute for Materials Science

  • Andrea F Young

    University of California, Santa Barbara, University of California Santa Barbara, University of California at Santa Barbara

  • Michael P Zaletel

    University of California, Berkeley

  • Ali Yazdani

    Princeton University