Observation of backscattering induced by magnetism in the topological hinge state of bismuth

ORAL

Abstract

We have investigated the effects of time-reversal symmetry breaking on the topological hinge state of bismuth. Using spectroscopic imaging and spin-polarized measurements with an STM, we have compared quasiparticle interference (QPI) occurring in the hinge state of a pristine bismuth bilayer with that occurring in the hinge state of a bilayer, which is terminated by ferromagnetic iron clusters. Our experiments on the decorated bilayer edge reveal an additional QPI branch that can be associated with spin-flip scattering across the Brioullin zone center between time-reversal band partners. The observed QPI characteristics exactly match with theoretical expectations for a topological edge state having one Kramer's pair of bands and, thus provide spectroscopic evidence for back scattering in the topological edge states of bismuth.

*This work is supported by the ONR, the Moore foundation, NSF-DMR, NSF-MRSEC & the Humboldt foundation.

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Presenters

  • Berthold Jaeck

    • Princeton University

Authors

  • Berthold Jaeck

    • Princeton University

  • Yonglong Xie

    • Princeton University
    • Department of Physics, Harvard University
    • Harvard University

  • Andrei Bernevig

    • Physics, Princeton University
    • Princeton Center for Theoretical Science, Princeton University
    • Princeton University
    • Department of Physics, Princeton university
    • Physics department, Princeton University

  • Ali Yazdani

    • Princeton University
    • Joseph Henry Laboratories & Department of Physics, Princeton University
    • Princeton Univ
    • Department of Physics, Princeton University