Evidence of Moiré Excitons in van der Waal(vdW) Heterostructure

ORAL

Abstract

We report spectroscopy evidence of interlayers excitons confined by a moire superlattice in hBN encapsulated MoSe2/WSe2 heterostructures with small twist angles. Low temperature photoluminescence(PL) measurement shows that interlayer exciton splits into multiple peaks with alternating circular polarization. We assign these peaks to the ground state and excited state excitons localized within a Moiré supercell and explain how the spatial variation of optical selection rule can give rise to multiple peaks with alternative circular polarization. Temperature dependence PL, twist angle dependence, and recombination dynamics all agrees with the localized exciton picture. Our results suggest the feasibility of engineering artificial excitonic crystal using vdW heterostructures for nanophotonics and quantum information applications.

–

Presenters

  • Kha Tran

    University of Texas at Austin, Department of Physics, University of Texas at Austin, TX 78712, United States

Authors

  • Kha Tran

    University of Texas at Austin, Department of Physics, University of Texas at Austin, TX 78712, United States

  • Galan Moody

    NIST

  • Fengcheng Wu

    Argonne National Lab, Condensed Matter Theory Center, University of Maryland, University of Maryland

  • Xiaobo Lu

    Beijing National Laboratory for Condensed Matter Physics, Beijing, China, Chinese Academy of Science, Physics, Washington University in St. Louis

  • Junho Choi

    University of Texas at Austin, Department of Physics, University of Texas at Austin, TX 78712, United States

  • Jiamin Quan

    University of Texas at Austin, Department of Physics, The University of Texas at Austin, Department of Physics, The University of Texas at Austin, USA

  • Akshay Singh

    Massachusetts Institute of Technology

  • Jacob S Embley

    University of Texas at Austin

  • André Zepeda

    University of Texas at Austin, Department of Physics, University of Texas at Austin, TX 78712, United States

  • Marshall Campbell

    University of Texas at Austin, Department of Physics, University of Texas at Austin, TX 78712, United States

  • Kyounghwan Kim

    Electrical and Computer Engineering department, The University of Texas at Austin, University of Texas at Austin

  • Amritesh Rai

    University of Texas at Austin

  • Travis Autry

    NIST

  • Daniel Sanchez

    University of Texas at Austin

  • 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

  • Nanshu Lu

    University of Texas at Austin

  • Sanjay Banerjee

    University of Texas at Austin

  • Emanuel Tutuc

    Electrical and Computer Engineering department, The University of Texas at Austin, University of Texas at Austin

  • Suenne Kim

    Hanyang University

  • Li Yang

    Physics, Washington University in St. Louis, Physics, Washington University, St. Louis

  • Kevin Silverman

    NIST

  • Allan MacDonald

    Department of Physics, University of Texas at Austin, University of Texas at Austin, The University of Texas at Austin

  • Xiaoqin (Elaine) Li

    University of Texas at Austin, University of Texas-Austin, The University of Texas at Austin, Department of Physics and Center for Complex Quantum Systems, Univ of Texas, Austin, Department of Physics, University of Texas at Austin, TX 78712, United States, Univ of Texas, Austin, Department of Physics, The University of Texas at Austin, Department of Physics, The University of Texas at Austin, USA