Scanning tunneling microscopy and spectroscopy study of graphene/NbSe<sub>2</sub> heterostructures

ORAL

Abstract

We investigate vertical van der Waals heterostructures consisting of monolayer graphene and bulk NbSe2. Due to interactions between the layers, coherent states in NbSe2, including charge density wave (CDW) and superconductivity, can be inherited by the graphene. The graphene/NbSe2 heterostructures were characterized with liquid helium temperature scanning tunneling microscopy. The graphene lattice, NbSe2 lattice and a moiré pattern due to their lattice mismatch are observed by scanning tunneling microscopy measurements. A CDW is also observed in the graphene, which is aligned with the NbSe2 lattice and 3 times its length, indicating it originates from the NbSe2. From the scanning tunneling spectroscopy measurements, a 1.1 meV superconducting gap is observed in the graphene. Vortices are also observed in a perpendicular magnetic field of 0.3 T. The superconductivity in the magnetic field is further confirmed by electrical transport measurements, which show a sharp drop in resistance at 6.2 K.

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Presenters

  • Zhiming Zhang

    • University of Arizona

Authors

  • Zhiming Zhang

    • University of Arizona

  • Shawulienu Kezilebieke

    • Aalto University

  • 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

  • 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

  • Peter Liljeroth

    • Aalto University

  • Brian LeRoy

    • University of Arizona