Topological current divider in a Chern insulator junction

ORAL

Abstract

A Chern insulator is a two-dimensional material that hosts chiral edge states produced by the combination of topology with time-reversal symmetry breaking. Such edge states are perfect one-dimensional conductors, which may exist not only on sample edges but on any boundary between two materials with distinct topological invariants (or Chern numbers). MnBi2Te4, a recently discovered van der Waals topological magnet, offers rich opportunities for Chern number engineering by means of combining Chern insulator and quantum Hall physics. In this talk, I will report a chiral edge-current divider based on Chern insulator junctions formed within the layered topological magnet MnBi2Te4. In a device containing a boundary between regions of different thicknesses, topological domains with different Chern numbers can coexist. At the domain boundary, a Chern insulator junction forms, where we identify a chiral edge mode along the junction interface. I will further demonstrate how this mode can be used to construct topological circuits in which the chiral edge current can be split, rerouted, or switched off by controlling the Chern numbers of the individual domains. Our results demonstrate MnBi2Te4 as an emerging platform for topological circuit design.

*Programmable Quantum Materials, an Energy Frontier Research Center funded by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), under award DE-SC0019443

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Publication: D. Ovchinnikov, J. Cai, et al., "Topological current divider in a Chern insulator junction", Nature Communications 13 (1), 1-6

Presenters

  • Dmitry Ovchinnikov

    • University of Washington

Authors

  • Dmitry Ovchinnikov

    • University of Washington

  • Jiaqi Cai

    • University of Washington

  • Zhong Lin

    • University of Washington

  • Zaiyao Fei

    • University of Washington

  • Zhaoyu Liu

    • University of Washington

  • Yongtao Cui

    • University of California, Riverside

  • David H Cobden

    • University of Washington

  • Jiun-Haw Chu

    • University of Washington
    • University of Washington, Seattle, Washington, USA

  • Cui-Zu Chang

    • The Pennsylvania State University
    • Pennsylvania State University

  • Di Xiao

    • University of Washington
    • 1. Department of Materials Science & Engineering, University of Washington, Seattle WA 98915 2. Department of Physics, University of Washington, Seattle WA 98915
    • Department of Materials Science & Engineering, Department of Physics, University of Washington; Pacific Northwest National Laboratory

  • Jiaqiang Yan

    • Oak Ridge National Laboratory
    • Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA

  • Xiaodong Xu

    • University of Washington