Observation of backscattering induced by magnetism in a topological edge state

Abstract

One of the predicted characteristics of helical topological boundary modes is the absence of backscattering when time-reversal symmetry (TRS) is preserved. While previous experiments have provided evidence for this topological protection, inducing backscattering by breaking TRS has yet to be demonstrated. We test this fundamental property by investigating quasiparticle scattering in the one-dimensional topological edge state of bismuth bilayers, coupled to ferromagnetic iron clusters, using a scanning tunneling microscope. Our experimental observations demonstrate that backscattering is induced by magnetism of iron clusters in these topological edge modes.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jun 29, 2020
Source ID
10.1073/pnas.2005071117

Entities

People

  • Ali Yazdani
  • Andrei Bernevig
  • Berthold Jäck
  • Yonglong Xie

Organizations

  • Army Research Office
  • Division of Materials Research
  • Gordon and Betty Moore Foundation
  • National Science Foundation Division of Mathematical Sciences
  • Office of Naval Research
  • Office of Science
  • Princeton University

Tags

Fields of Study

  • Physics

Readers

  • Materials Science and Engineering.
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  • Solar Physics