Asymmetric Josephson Effect in WTe2 Weyl Semimetal

POSTER

Abstract

WTe2 is predicted to be Type-II Weyl semimetal, hosting Weyl nodes at the contact of electron and hole pockets in a momentum space. We studied electronic transport properties of the Josephson effects mediated by WTe2 Weyl semimetal. Proximity Josephson junctions were fabricated by depositing a pair of superconducting electrodes on exfoliated WTe2 layers. Perpendicular magnetic field dependence of Josephson critical current, Ic(B), (so-called Fraunhofer pattern) exhibited anomalous behaviors: 1) Slow decay of Ic lobes as B increases indicates that the transport is dominated by edge channels of WTe2 layer. 2) Asymmetric Fraunhofer pattern, i.e. Ic(B)≠Ic(-B), suggests asymmetric Fermi velocity of each edge channel due to the inversion symmetry breaking of WTe2.

*Y.-B.C. and G.-H.L. were supported by the National Research Foundation of Korea(NRF) Grant funded by the Korean Government (No. 2016R1A5A1008184). K.C.F. were funded by Raytheon BBN Technologies. C.-Z.C. and K.T.L. were supported by HKRGC and Croucher Foundation through HKUST3/CRF/13G, 602813, 605512, 16

Presenters

  • Yongbin Choi

    • Department of Physics, POSTECH

Authors

  • Yongbin Choi

    • Department of Physics, POSTECH

  • Chui-Zhen Chen

    • Department of Physics, Hong Kong University of Science and Technology

  • Kumari Gaurav Rana

    • Max Plank Institute for Microstructure Physics
    • Max Planck Institute of Microstructure Physics

  • Mazhar Ali

    • Max Planck Institute of Microstructure Physics
    • Max Plank Institute for Microstructure Physics
    • Max Planck Institute of Microstructure physics

  • Kam Tuen Law

    • Hong Kong Univ of Sci & Tech
    • Department of Physics, Hong Kong University of Science and Technology
    • Physics, Hong Kong Univ of Sci & Tech
    • Hong Kong University of Science and Technology
    • Physics Department, Hong Kong Univ of Sci & Tech

  • Kin Chung Fong

    • BBN Technology - Massachusetts
    • BBN
    • Raytheon BBN Technologies, Quantum Information Processing Group
    • Raytheon BBN Technology

  • Gil-Ho Lee

    • Department of Physics, POSTECH
    • Physics, Pohang University of Science and Technology
    • POSTECH