Probing band structure renormalization in 2D semiconductors induced by external dielectric screening through angle-resolved photoemission spectroscopy

ORAL

Abstract

We investigate the effect of dielectric screening by the external environment on the electronic states in the two-dimensional (2D) semiconductor WS2 using angle-resolved photoemission spectroscopy (ARPES). As has been previously reported from optical spectroscopy of monolayer WS2 [1], an increase in environmental screening from the presence of graphene can lead to a ~100 meV reduction of the bandgap. Our ARPES study of monolayer WS2 partially placed on h-BN and graphene, however, reveals that the dispersion of the valence band is essentially unchanged (< 10 meV shifts) when screening by graphene is present. Thus the screening-induced band renormalization appears to lead only to a rigid shift, rather than a restructuring of the valence band. We compare this experimental finding with theory based on GΔW calculations, including material-realistic frequency and momentum dependent screening due to the substrate. In agreement with experiment, theory predicts the primary effect of bandgap renormalization along with a scissor-like shift of all electronic states. We discuss the physical origin of this result and its implication for the use of controlled changes in the environment to tune the band structure of 2D semiconductors.
[1] A. Raja et al. Nature Commun., 8, 15251 (2017)

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Presenters

  • Lutz Waldecker

    Department of Applied Physics, Stanford University, Stanford, California, 94305 USA, Stanford University and SLAC National Laboratory

Authors

  • Lutz Waldecker

    Department of Applied Physics, Stanford University, Stanford, California, 94305 USA, Stanford University and SLAC National Laboratory

  • Archana Raja

    Department of Applied Physics, Stanford University, Stanford, California, 94305 USA, University of California, Berkeley

  • Malte Roesner

    University of Southern California, University of Southern California and CCQ, Flatiron Institute

  • Christina Steinke

    University of Bremen

  • Roland Koch

    Advanced Light Source, Lawrence Berkeley National Laboratory, Lawrence Berkeley National Laboratory, Advanced Light Source, E. O. Lawrence Berkeley National Laboratory

  • Aaron Bostwick

    Advanced Light Source, E.O. Lawrence Berkeley National Lab, Berkeley, CA 94720, USA, Advanced Light Source, Lawrence Berkeley National Laboratory, ALS, Lawrence National Berkeley Laboratory, Advanced Light Source, Lawrence Berkeley National Lab, Lawrence Berkeley National Laboratory, Advanced Light Source (ALS), E. O. Lawrence Berkeley National Laboratory, USA, Advanced Light Source, E. O. Lawrence Berkeley National Laboratory

  • Chris Jozwiak

    Advanced Light Source, E.O. Lawrence Berkeley National Lab, Berkeley, CA 94720, USA, Advanced Light Source, Lawrence Berkeley National Laboratory, ALS, Lawrence National Berkeley Laboratory, Advanced Light Source, Lawrence Berkeley National Lab, Lawrence Berkeley National Laboratory, Lawrence Berkeley National Lab, Berkeley, USA, Advanced Light Source (ALS), E. O. Lawrence Berkeley National Laboratory, USA, Advanced Light Source, E. O. Lawrence Berkeley National Laboratory

  • 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

  • Eli Rotenberg

    Advanced Light Source, E.O. Lawrence Berkeley National Lab, Berkeley, CA 94720, USA, Advanced Light Source, Lawrence Berkeley National Laboratory, ALS, Lawrence National Berkeley Laboratory, Advanced Light Source, Lawrence Berkeley National Lab, Lawrence Berkeley National Laboratory, Advanced Light Source (ALS), E. O. Lawrence Berkeley National Laboratory, USA, Advanced Light Source, E. O. Lawrence Berkeley National Laboratory

  • Tim Wehling

    Institute for Theoretical Physics, Bremen Center for Computational Material Science, University of Bremen, University of Bremen

  • Tony F Heinz

    Stanford University & SLAC National Accelerator Laboratory, Department of Applied Physics, Stanford University, Stanford, California, 94305 USA, Applied Physics, Stanford University, Stanford University and SLAC National Laboratory, Stanford University, Stanford University & SLAC