Shubnikov-de Haas Oscillations in bilayer MoSe<sub>2</sub>: effective mass and carrier density dependent quantum Hall states sequence

ORAL

Abstract

We report magnetotransport studies of high-mobility electrons in dual-gated bilayer MoSe2 Hall-bars. Samples are fabricated using dry-transfer techniques, where an exfoliated MoSe2 bilayer is encapsulated in hexagonal boron-nitride dielectrics. The introduction of metal bottom-contacts coupled with electrostatic doping of the contact regions yields low-resistance n-type contacts down to low temperatures (0.3 K). The measured longitudinal resistance shows clear Shubnikov-de Haas (SdH) oscillations, and quantum Hall states (QHSs) developing at high magnetic fields. The temperature dependence of the SdH oscillations amplitude allows to extract an electron effective mass of 0.8me. The QHSs sequence shows transitions from even to odd filling factors as a function of electron density, which indicate the Zeeman to cyclotron energy ratio changes with density, likely because of electron-electron interaction. The QHSs are insensitive to an applied in-plane magnetic field, which suggest the electron spins are locked perpendicular to the MoSe2 plane because of strong spin-orbit interaction.

*This work was supported by the National Science Foundation Grant EECS-1610008, and Intel Corp. A part of this work was performed at NHMFL, supported by NSF Coop. Agmt. DMR-1157490 and the State of Florida

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Presenters

  • Stefano Larentis

    • Univ of Texas, Austin

Authors

  • Stefano Larentis

    • Univ of Texas, Austin

  • Hema Movva

    • The University of Texas at Austin
    • Univ of Texas, Austin

  • Babak Fallahazad

    • Univ of Texas, Austin
    • Electrical and Computer Engineering, The University of Texas at Austin

  • Kyounghwan Kim

    • The University of Texas at Austin
    • Univ of Texas, Austin
    • Electrical and Computer Engineering, The University of Texas at Austin

  • Armand Behroozi

    • Univ of Texas, Austin

  • Takashi Taniguchi

    • National Institute for Materials Science
    • NIMS
    • National Institute for Material Science
    • Advanced Materials Laboratory, National Institute for Materials Science
    • National Institute of Materials Science
    • Research Center for Functional Materials, National Institute for Materials Science
    • National Institute for Materials Science (NIMS
    • Advanced Materials Laboratory, NIMS
    • National Institute for Materials Science, Advanced Materials Laboratory
    • National Institue for Materials Science
    • National Institute of Material Science
    • National Institute for Matericals Science
    • Advanced Materials Laboratory
    • National Institute for Materials Science, 1-1 Namiki
    • NIMS-Japan

  • Kenji Watanabe

    • National Institute for Materials Science
    • NIMS
    • National Institute for Material Science
    • Advanced Materials Laboratory, National Institute for Materials Science
    • National Institute of Materials Science
    • Research Center for Functional Materials, National Institute for Materials Science
    • National Institute for Materials Science (NIMS
    • Advanced Materials Laboratory, NIMS
    • National Institute for Materials Science, Advanced Materials Laboratory
    • National Institue for Materials Science
    • National Institute of Material Science
    • National Institute for Matericals Science
    • Advanced Materials Laboratory
    • National Institute for Materials Science, 1-1 Namiki
    • Advanced materials laboratory, National institute for Materials Science
    • NIMS-Japan

  • Sanjay Banerjee

    • Electrical and Computer Engineering, University of Texas at Austin
    • Univ of Texas, Austin
    • The University of Texas at Austin

  • Emanuel Tutuc

    • The University of Texas at Austin
    • Department of Electrical and Computer Engineering, The University of Texas at Austin
    • Univ of Texas, Austin
    • Electrical and Computer Engineering, The University of Texas at Austin