Edge Channels of Broken Symmetry Quantum Hall States in Graphene probed by Atomic Force Microscopy

ORAL

Abstract

The quantum Hall effect, a topologically non-trivial quantum phase has brought into focus the concept of topological order in physics. The topologically protected quantum Hall edge states are the essential features of the QH effect, however microscopic local probe studies of edge states have been conducted with limited success. The QH edge states in graphene are special since they emerge from four-fold nearly-degenerate Landau levels. In this talk, we present a microscopic study a of the QH edge states originating from the broken symmetry states of zeroth LL in graphene using AFM. The KPFM detects the chemical potential transitions when Landau levels are being filled or empty as a function of back gate potential and show the same fidelity for Landau level spectroscopy as STS measurements. In particular broken symmetry states can be resolved at integer filling factors ν=0, ±1 inside the N=0 Landau level manifold, showing the lifting of the graphene four-fold degeneracy due to spin and valley. The edge channels emerging from integer filling factors are spatially mapped across the quantum Hall edge using AFM. The microscopic properties by scanning probe measurement of quantum Hall edge channels can be correlated with macroscopic properties measured with in-situ magnetotransport.

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Presenters

  • Sungmin Kim

    • Physical Measurement Laboratory, National Institute of Standards and Technology

Authors

  • Sungmin Kim

    • Physical Measurement Laboratory, National Institute of Standards and Technology

  • Johannes Schwenk

    • École polytechnique fédérale de Lausanne

  • Daniel T Walkup

    • Physical Measurement Laboratory, National Institute of Standards and Technology

  • Yihang Zeng

    • Department of Physics, Columbia University
    • Columbia Univ

  • Fereshte Ghahari Kermani

    • Department of Physics and Astronomy, George Mason University

  • Son Le

    • Physical Measurement Laboratory, National Institute of Standards and Technology
    • National Institute of Standards and Technology
    • Physical Measurement Laboratory, National Institute of Standards and Technology & Theiss Research
    • Theiss Research, Inc., La Jolla, CA and NIST, Gaithersburg, MD

  • Marlou Slot

    • Physical Measurement Laboratory, National Institute of Standards and Technology
    • National Institute of Standards and Technology

  • Julian Berwanger

    • Institute of Experimental and Applied Physics, University of Regensburg

  • Steven Blankenship

    • Physical Measurement Laboratory, National Institute of Standards and Technology

  • Kenji Watanabe

    • National Institute for Materials Science
    • National Institute for Materials Science, Japan
    • National Institure for Materials Science
    • Advanced Materials Laboratory, National Institute for Materials Science
    • NIMS
    • National Institute of Materials Science
    • National Institute for Materials Science (NIMS)
    • Research Center for Functional Materials, National Institute for Materials Science
    • National Institute for Materials Science,1-1 Namiki
    • National Institute of Material Science
    • National Institute for Materials Science, Tsukuba, Japan
    • Research Center for Functional Materials, NIMS
    • National Institute of Materials Science, Tsukuba, Japan
    • National Institude for Materials Science
    • National Institute for Materials Science, Tsukuba, Ibaraki, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, Tsukuba 305-0044, Japan
    • International Center for Materials Nanoarchitectonics, National Institute for Materials
    • NIMS - Japan
    • National Institute for Materials Science ,Japan
    • National Institute for Materials Science, Tsukuba, 305-0044, Ibaraki, Japan
    • National Institute for Material Science
    • National Institute for Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science Japan
    • NIMS Tsukuba
    • National Institute for Materials Science, Research Center for Functional Materials, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Materials Science: Namiki, Tsukuba, Ibaraki, JP
    • National Institue for Material Science
    • National Institute for Materials Science,1-1 Namiki, Tsukuba, 305-0044, Japan
    • Materials, NIMS
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, Research Center for Functional Materials, National In
    • Research Center for Functional Materials, Japan
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • International Center for Materials nanoarchtectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
    • NIMS Suguba
    • NIMS, Tsukuba, Japan
    • National Institute for Materials Science, Namiki 1-1, Tsukuba, 305-0044, Ibaraki, Japan
    • National institute of material science
    • Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
    • Advanced Materials Laboratory, NIMS
    • Research Center for Functional Materials, National Institute for Materials Science, Ibaraki, Japan
    • National Institute for Materials Science, Research Center for Functional Materials
    • National Institute of Material Science, Japan
    • Tsukuba, National Institute for Materials Science

  • Takashi Taniguchi

    • National Institute for Materials Science
    • National Institute for Materials Science, Japan
    • National Institure for Materials Science
    • Advanced Materials Laboratory, National Institute for Materials Science
    • NIMS
    • National Institute of Materials Science
    • National Institute for Materials Science (NIMS)
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • National Institute for Materials Science,1-1 Namiki
    • National Institute of Material Science
    • National Institute for Materials Science, Tsukuba, Japan
    • International Center for Materials Nanoarchitectonics, NIMS
    • Research Center for Functional Materials, National Institute for Materials Science
    • National Institute of Materials Science, Tsukuba, Japan
    • National Institude for Materials Science
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba 305-0044, Japan
    • International Center for Materials Nanoarchitectonics, National Institute for Materials
    • NIMS - Japan
    • National Institute for Materials Science ,Japan
    • National Institute for Materials Science, Tsukuba, 305-0044, Ibaraki, Japan
    • National Institute for Material Science
    • National Institute for Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science Japan
    • 8International Center for Materials Nanoarchitectonics
    • NIMS Tsukuba
    • National Institute for Materials Science: Namiki, Tsukuba, Ibaraki, JP
    • National Institue for Material Science
    • National Institute for Materials Science,1-1 Namiki, Tsukuba, 305-0044, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, Research Center for Functional Materials, National In
    • Research Center for Functional Materials, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
    • International Center for Material Nanoarchitectonics, National Institute for Materials Science
    • International Center for Materials Nanoarchitectonics
    • NIMS Suguba
    • NIMS, Tsukuba, Japan
    • National Cheng Kung University
    • National Institute for Materials Science, Namiki 1-1, Tsukuba, 305-0044, Ibaraki, Japan
    • National institute of material science
    • Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
    • Advanced Materials Laboratory, NIMS
    • National Institute for Materials Science, International Center for Materials Nanoarchitectonics
    • National Institute of Material Science, Japan
    • Tsukuba, National Institute for Materials Science

  • Franz J Giessibl

    • Institute of Experimental and Applied Physics, University of Regensburg

  • Nikolai Zhitenev

    • Physical Measurement Laboratory, National Institute of Standards and Technology

  • Cory Dean

    • Columbia University
    • Department of Physics, Columbia University
    • Physics, Columbia University
    • Columbia Univ

  • Joseph Stroscio

    • Physical Measurement Laboratory, National Institute of Standards and Technology
    • National Institute of Standards and Technology