Studying the non-abelian even-denominator state in Bernal-stacked bilayer graphene by scanning tunneling microscope

ORAL

Abstract

Non-abelian anyons have drawn interest from physicists because of their potential application as qubits in topological quantum computation. The even-denominator fractional quantum Hall (FQH) states are candidates for achieving non-abelian anyons. In this talk, I will discuss our recent scanning tunneling microscope (STM) measurement of the FQH states in the N=1 Landau levels of bilayer graphene. By measuring thermodynamic gaps locally, we find energy gaps for the even-denominator FQH states to be around 30 K at 14 T, larger by one or two orders of magnitude than prior transport and penetration capacitance measurements in other related systems. We find supporting evidence for the even-denominator states to be non-abelian by observing its Levin-Halperin daughter states. We also measure the influence of local single-atom defects on the even-denominator state gaps and identify the intrinsic FQH gaps with sizes consistent with theoretical calculations. The large gap reported in this study makes bilayer graphene an ideal platform for the future realization of topological qubits based on non-abelian anyons.

*This work is supported by grants from DOE, Moore Foundation, NSF-DMR, NSF-MRSEC, and ONR.

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Publication: 1. Yuwen Hu, Yen-Chen Tsui, Minhao He, Umut Kamber, Taige Wang, Amir S. Mohammadi, Kenji Watanabe, Takashi Taniguchi, Zlatko Papic, Michael P. Zaletel, Ali Yazdani, arXiv: 2308. 05789 (2023)

Presenters

  • Yuwen Hu

    • Princeton University

Authors

  • Yuwen Hu

    • Princeton University

  • Yen-Chen Tsui

    • Princeton University

  • Minhao He

    • Princeton University

  • Umut Kamber

    • Princeton University

  • Taige Wang

    • University of California, Berkeley

  • Amir Shapour Mohammadi

    • Princeton University

  • Kenji Watanabe

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

  • Takashi Taniguchi

    • Kyoto Univ
    • National Institute for Materials Science
    • Research Center for Materials Nanoarchitectonics
    • Research Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • National Institute for Materials Sciences
    • NIMS
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science
    • International Center for Materials Nanoarchitectonics, NIMS, Japan
    • International Center for Materials Nanoarchitectonics, Tsukuba
    • National Institue for Materials Science
    • Kyoto University
    • National Institute of Materials Science
    • International Center for Materials Nanoarchitectonics and National Institute for Materials Science

  • Zlatko Papic

    • Univ of Leeds

  • Michael P Zaletel

    • University of California, Berkeley
    • University of Berkerley
    • UC Berkeley

  • Ali Yazdani

    • Princeton University