Imaging Spin-Polarized Scattering of Topological Surface States

ORAL

Abstract

Surface states of topological insulators are comprised of Dirac fermions protected from backscattering due to alignment of spin and momentum, a property characteristic of relativistic particles. We realize topological states on the surface of pure antimony, a fundamental parent matrix of various topological insulator compounds. With low-temperature scanning tunneling microscopy (STM), we directly visualize spin-polarized scattering of surface state electrons with sub-atomic precision around surface and subsurface defects. These results link closely to angle-resolved photoemission spectroscopy (ARPES) studies on the same materials, unambiguously measure the spin-protection of topologically ordered states, and access a striking transition to a single unpaired Dirac species.

–

Authors

  • W. Ko

    Department of Physics and SIMES, Stanford University

  • Kenjiro K. Gomes

    Department of Physics and SIMES, Stanford University

  • W. Mar

    Department of Physics and SIMES, Stanford University

  • Yulin Chen

    Department of Physics and SIMES, Stanford University, Dept. Applied Physics, Stanford Univ, SLAC National Accelerator Laboratory

  • Zhi-Xun Shen

    Stanford University, Department of Physics and SIMES, Stanford University, Dept. Applied Physics, Stanford Univ, Geballe Laboratory for Advanced Materials, Stanford University

  • H. C. Manoharan

    Department of Physics and SIMES, Stanford University, Stanford University