Tunnelling spectroscopy of localized states in WS<sub>2</sub> based van der Waals heterostructures

POSTER

Abstract

Defects in semiconductors and dielectrics can provide rich physics with technological potential such as quantum photon emission, spin control and they might be potential platforms for realizing quantum entanglement. In transition metal dichalcogenides, defects have been found to play important role as they affect the doping and the spin-valley relaxation dynamics. Herein we study localized states in WS2 by means of tunnelling spectroscopy using van der Waals heterostructures of h-BN/graphene/WS2/metal. The monolayer graphene electrodes provide for weak screening of electric-fields, which allows us to tune the chemical potential of WS2 with the back-gate. The obtained conductance maps as a function of bias and gate voltage reveal single-electron transistor behaviour (Coulomb blockade) with a rich set of transport features like excited states and negative differential resistance regimes. Moreover, by applying a perpendicular magnetic field, we study the spin ground- and excited states of single defects.

*This work is part of the Organisation for Scienti�c Research (NWO) and the Ministry of Education, Culture,
and Science (OCW).Growth of hexagonal boron nitride crystals was supported by the Elemental Strategy Initiative conducted by the MEXT, Japan and the CREST (JPMJCR15F3), JST.

Presenters

  • Nikos Papadopoulos

    • Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, Delft 2628 CJ, The Netherlands
    • TU Delft

Authors

  • Nikos Papadopoulos

    • Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, Delft 2628 CJ, The Netherlands
    • TU Delft

  • Pascal Gehring

    • Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, Delft 2628 CJ, The Netherlands

  • Takashi Taniguchi

    • National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305 0044, Japan
    • National Institute for Materials Science
    • Advanced Materials Laboratory, National Institute for Materials Science, , 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science, 1-1 Namiki, Tsukuba 305-0044
    • National Institute of Materials Science
    • NIMS, Japan
    • Advanced Materials Laboratory, NIMS
    • National Institute for Materials Science, Tsukuba, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science
    • National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0044, Japan
    • National Institute for Materials Science (NIMS)
    • NIMS Tsukuba
    • NIMS
    • National Institute for Material Science
    • National Institute for Materials Science, Japan
    • National Institute for Materials Science, 1-1 Namiki, Tsukuba, Japan
    • National Institute for Materials Science , Japan
    • Advanced Materials Laboratory, National Institute for Materials Science, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
    • National Institute for Materials Science, Tsukuba, Ibaraki 305- 0044, Japan
    • National Institute for Material Science - Japan
    • National Institute for Materials Science, Namiki Tsukuba Ibaraki, Japan
    • National Institute of Material Science
    • Advanced Material Lab, NIMS
    • Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Ibaraki, Japan
    • National Institute for Materials Science, Tsukuba
    • 1-1 Namiki, Tsukuba, National Institute for Materials Science
    • NIMS/Tsukuba
    • National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044 Japan
    • National Institute for Materials Science, Namiki, 305-0044, Japan
    • National Institute for Material Science, Japan
    • Advanced Materials Laboratory, NIMS, Japan
    • Advanced Materials Labaratory, National Institute for Materials Science
    • National Institute of Material Science, 1-1 Namiki, Tsukuba, Ibaraki 205-0044, Japan
    • National Institute of Materials Science, Japan

  • Kenji Watanabe

    • National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305 0044, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Materials Science
    • Advanced Materials Laboratory, National Institute for Materials Science, , 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science, 1-1 Namiki, Tsukuba 305-0044
    • National Institute of Materials Science
    • NIMS, Japan
    • Advanced Materials Laboratory, NIMS
    • National Institute for Materials Science, Tsukuba, Japan
    • National Institute for Materials Science, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science
    • National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0044, Japan
    • National Institute for Materials Science (NIMS)
    • NIMS Tsukuba
    • National Institute for Materials Science (Japan)
    • NIMS
    • National Institute for Material Science
    • National Institute for Materials Science, 1-1 Namiki, Tsukuba, Japan
    • National Institute for Materials Science , Japan
    • National Institute for Materials Science, Namiki 1-1, Tsukuba, Ibaraki 305-0044, Japan.
    • Advanced Materials Laboratory, National Institute for Materials Science, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
    • National Institute for Materials Science, Tsukuba, Ibaraki 305- 0044, Japan
    • National Institute for Material Science - Japan
    • National Institute for Materials Science, Namiki Tsukuba Ibaraki, Japan
    • National Institute of Material Science
    • Advanced Material Lab, NIMS
    • Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Japan
    • Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Ibaraki, Japan
    • National Institute for Materials Science, Tsukuba
    • 1-1 Namiki, Tsukuba, National Institute for Materials Science
    • NIMS/Tsukuba
    • National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044 Japan
    • National Institute for Materials Science, Namiki, 305-0044, Japan
    • National Institute for Material Science, Japan
    • Advanced Materials Laboratory, NIMS, Japan
    • Columbia University
    • Advanced Materials Labaratory, National Institute for Materials Science
    • National Institute of Material Science, 1-1 Namiki, Tsukuba, Ibaraki 205-0044, Japan
    • National Institute of Materials Science, Japan

  • Herre S.J. van der Zant

    • Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, Delft 2628 CJ, The Netherlands
    • TU Delft
    • Delft University of Technology

  • Gary Steele

    • Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, Delft 2628 CJ, The Netherlands
    • Delft University of Technology