Scanning tunneling microscopy study of robust fractional quantum Hall states in Bernal-stacked bilayer graphene

ORAL

Abstract

Fractional quantum Hall states (FQHs) emerge when a 2D electron system is subjected to a strong magnetic field. We performed millikelvin scanning tunneling microscopy (STM) study of the FQHs in Bernal-stacked bilayer graphene. A robust sequence of odd-denominator FQHs are observed, and their charge excitation gaps are characterized. Moreover, we also detected even-denominator FQHs in the lowest Landau levels, highlighting the extra orbital degeneracy for the many-body states. With the imaging power of STM, we can study the spatial variation of these FQH states, and the local excitations when these FQHs experience a defect potential. Our study helps with understanding the charge excitations of these FQHs and opens an opportunity to image anyons.

*We thank Moore, ONR, DOE, and ARO-MURI for funding support.

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Presenters

  • Yen-Chen Tsui

    • Princeton University

Authors

  • Yen-Chen Tsui

    • Princeton University

  • Yuwen Hu

    • Princeton University

  • Minhao He

    • Princeton University

  • Umut Kamber

    • Princeton University

  • 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

  • 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

  • Ali Yazdani

    • Princeton University