Bilayer silicene in a magnetic field: spin localization and its effect on the integer and fractional Hall conductivity

ORAL

Abstract

The Hall conductivity of many condensed matter systems presents step structure when a uniform perpendicular magnetic field is applied. We report the emergence of fractions of the Hall conductivity due to the grouping in pairs of an electron with a bilayer silicene sublattice site due to strong spin-orbit coupling. The collective behavior of this pairing causes the conductivity to exhibit steps of e2/h or 4/5 e2/h high for the low-lying spectrum, depending on the dominating sublattices of Landau levels. This coexistence of integer and fractional Quantum Hall States arises from the interplay of lattice geometry, atomic interaction, spin-orbit coupling, and external magnetic field. We also report the significant effect of an external electric field on the evolution of integer and fractional quantum Hall effects.

*This material is based upon work supported by the Air Force Office of Scientific Research (AFOSR) under award number FA2386-18-1-0120. We acknowledge the support from the DoD Lab-University Collaborative Initiative (LUCI) Program and the Air Force Research Laboratory (AFRL) through Grant No. 12530960.

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Presenters

  • Thi Nga Do

    • Dept. of Physics, National Cheng Kung University

Authors

  • Thi Nga Do

    • Dept. of Physics, National Cheng Kung University

  • Godfrey Gumbs

    • Hunter College of the City University of New York, Department of Physics and Astronomy
    • Hunter college
    • Department of Physics & Astronomy, Hunter College of CUNY, New York, NY, USA
    • Hunter College, City University of New York, New York, NY
    • Physics and Astronomy, Hunter College/CUNY
    • Department of Physics and Astronomy, Hunter College of the City University of New York
    • Hunter College, CUNY
    • Physics Department, Hunter College/CUNY

  • Pohsin Shih

    • Dept. of Physics, National Cheng Kung University

  • Danhong Huang

    • Air Force Research Lab - Kirtland
    • Physics, University of New Mexico
    • Air Force Research Labs.
    • Kirtland Airforce Base, Air Force Research Laboratory, Albuquerque, NM
    • Advanced E/O Space Sensors Group, Air Force Research Laboratory
    • US Air Force Research Laboratory
    • Space Vehicles Directorate, Kirtland AFB, Air Force Research Laboratory