Spontaneous defect formation on the polar surface of giant Rashba semiconductors BiTeX

 · Invited

Abstract

Defects in semiconductors are crucial for the performance of modern electronics. Although there are tremendous progress on theoretical understanding of defect formation and kinetics in functional materials, visualizing the kinetics of the defect formation remains a great challenge. Herein, we report an exciting discovery of spontaneous formation of point defects below room temperature on the surface of polar semiconductors BiTeX (X=Cl, Br and I), where giant Rashba splitting of bulk bands was reported. The defect density increases over three order of magnitudes when the surface temperature increases from ~10 K to room temperature. Our scanning tunneling microscopy studies reveal formation of Frenkel pairs of Bi vacancies and interstitial Bi atoms, followed by the formation of BiTe antisites. Combined with first principle calculations, our results reveal a significant reduction of formation energy of Frenkel pairs due to surface band bending of polar surface. Our results demonstrate a dramatic modulation of defect formation via surface bending of polar surface, which is crucial for the potential technological application of giant Rashba systems.

*The STM works at Rutgers were supported by NSF Grant No. DMR-1506618. S.B.Z. was supported by the Department of Energy under Grant No. DE-SC0002623. D.W. was supported by NSF under Grant No. EFMA-1542789. The supercomputer time was provided by the CCNI at RPI and NERSC under DOE Contract No. DE-AC02-05CH11231. The single crystal synthesis works were supported by NSF under Grant No. DMR-1629059.

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Presenters

  • Weida Wu

    • Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854, USA
    • Department of Physics and Astronomy, Rutgers University
    • Physics and Astronomy, Rutgers University, New Brunswick
    • Rutgers University, New Brunswick

Authors

  • Weida Wu

    • Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854, USA
    • Department of Physics and Astronomy, Rutgers University
    • Physics and Astronomy, Rutgers University, New Brunswick
    • Rutgers University, New Brunswick

  • Wenhan Zhang

    • Department of Physics and Astronomy, Rutgers University
    • Physics and Astronomy, Rutgers University, New Brunswick

  • Damien West

    • Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute

  • Chen Chen

    • Department of Physics and Astronomy, Rutgers University
    • Physics and Astronomy, Rutgers University, New Brunswick

  • Jinwoong Kim

    • Rutgers University, New Brunswick
    • Department of Physics and Astronomy, Rutgers University, Piscataway, NJ-08854, USA
    • Physics and Astronomy, Rutgers University, New Brunswick
    • Department of Physics and Astronomy, Rutgers University, New Jersey

  • Sang-Wook Cheong

    • Rutgers University
    • Department of Physics and Astronomy, Rutgers University
    • Rutgers University, New Brunswick
    • Rutgers Center for Emergent Materials and Department of Physics & Astronomy, Rutgers University
    • Center for Quantum Materials Synthesis and Department of Physics and Astronomy, Rutgers, the State University of New Jersey
    • Department of Physics, Rutgers University
    • Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ
    • Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854, USA
    • Physics, Rutgers University
    • Physics and Astronomy, Rutgers University, New Brunswick
    • Department of Physics and Astronomy, Rutgers University, New Jersey
    • Rutgers University, Physics and Astronomy, and Laboratory for Pohang Emergent Materials and Max Plank POSTECH Center for Complex Phase Materials, Pohang University of Science
    • RCEM, Department of Physics and Astronomy, Rutgers U.
    • Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University
    • Department of Physics and Astronomy, 136 Frelinghuysen Road, Piscataway, New Jersey 08854, USA, Rutgers Center for Emergent Materials

  • David Vanderbilt

    • Rutgers University, New Brunswick
    • Department of Physics and Astronomy, Rutgers University
    • Department of Physics and Astronomy, Rutgers University, Piscataway, NJ-08854, USA
    • Physics and Astronomy, Rutgers University, New Brunswick
    • Department of Physics and Astronomy, Rutgers University, New Jersey
    • Rutgers University, USA
    • Rutgers Univ
    • Physics and Astronomy, Rutgers University, Piscataway, NJ, United States
    • Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, USA

  • Shengbai Zhang

    • Physics, Rensselaer Polytechnic Institute
    • Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute
    • Rensselaer Polytechnic Institute
    • Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute