APS Logo

Valley Phonons and Exciton Complexes in a Monolayer Semiconductor

ORAL

Abstract

The coupling between spin, charge, and lattice degrees of freedom plays an important role in a wide range of fundamental phenomena. Monolayer semiconducting transitional metal dichalcogenides have emerged as an outstanding platform for studying these coupling effects because they possess unique spin-valley locking physics for hosting rich excitonic species and the reduced screening for strong Coulomb interactions. Here, we report the observation of multiple valley phonons – phonons with momentum vectors pointing to the corners of the hexagonal Brillouin zone, in monolayer WSe2. We find that these valley phonons lead to efficient intervalley scattering of quasi particles in both exciton formation and relaxation. This leads to a series of photoluminescence peaks as valley phonon replicas of dark trions, and the identification of intervalley exciton near charge neutrality.

–

Presenters

  • Minhao He

    University of Washington

Authors

  • Minhao He

    University of Washington

  • Pasqual Rivera

    University of Washington

  • Dinh Van Tuan

    University of Rochester

  • Nathan P Wilson

    Department of Physics, University of Washington, University of Washington

  • Min Yang

    University of Rochester, Department of Electrical and Computer Engineering, University of Rochester

  • Takashi Taniguchi

    National Institute for Materials Science, Japan, National Institute for Material Science, National Institute for Materials Science, National Institute for Materials Science, Tsukuba, Research Center for Functional Materials, NIMS, nims, Advanced Materials Laboratory, National Institute for Materials Science, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, NIMS, National Institute for Material Science - Japan, NIMS Tsukuba, National Institute for Materials Science, Namiki 1-1, Ibaraki 305-0044, Japan., National Institute for Materials Science (NIMS), National Institute for Materials Science,Tsukuba, Ibaraki 305-0047, Japan, Advanced Materials Laboratory, NIMS, Japan, National Institute for Materials Science,1-1 Namiki, Tsukuba, 305-0044, Japan, National Institute of Materials Science, National Institute for Materials Science, University of Tsukuba, National Institute for Materials Science, Tsukuba, Japan, National Institue for Material Science, Tsukuba, Advanced Materials Laboratory, NIMS, Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba 305-0044, Japan, Advanced Matrials Lab, NIMS, National Institute for Material Science, Tsukuba, Japan, National institute for materials science, NIMS-Tsukuba, NIMS, Japan, National Institute for Materials Science, Namiki Tsukuba Ibaraki, Japan, Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Japan, NIMS Japan, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan, Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Ibaraki, Japan, Advanced Materials Laboratory, National Institute of Materials Science, Advanced Materials Laboratory, National Institute for Materials Science 1-1 Namiki, Tsukuba, 305-0044, Japan, National Institute of Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan, National Institute for Material Science (Japan), Physics, NIMS, National Institute of Materials Science, Japan, National Institute of Materials Science, Tsukuba, Ibaraki 305-0044, Japan, NIMS - Tsukuba

  • Kenji Watanabe

    National Institute for Materials Science, Japan, National Institute for Material Science, National Institute for Materials Science, National Institute for Materials Science, Tsukuba, Research Center for Functional Materials, NIMS, nims, Advanced Materials Laboratory, National Institute for Materials Science, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan, NIMS, National Institute for Material Science - Japan, NIMS Tsukuba, National Institute for Materials Science, Namiki 1-1, Ibaraki 305-0044, Japan., National Institute for Materials Science (NIMS), National Institute for Materials Science,Tsukuba, Ibaraki 305-0047, Japan, Advanced Materials Laboratory, NIMS, Japan, National Institute for Materials Science,1-1 Namiki, Tsukuba, 305-0044, Japan, National Institute of Materials Science, National Institute for Materials Science, University of Tsukuba, National Institute for Materials Science, Tsukuba, Japan, National Institute for Material Science, Japan, National Institue for Material Science, Tsukuba, Advanced Materials Laboratory, NIMS, Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba 305-0044, Japan, Advanced Matrials Lab, NIMS, National Institute for Material Science, Tsukuba, Japan, National institute for materials science, NIMS-Tsukuba, NIMS, Japan, National Institute for Materials Science, Namiki Tsukuba Ibaraki, Japan, NIRM, Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Japan, NIMS Japan, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan, Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Ibaraki, Japan, Advanced Materials Laboratory, National Institute of Materials Science, Advanced Materials Laboratory, National Institute for Materials Science 1-1 Namiki, Tsukuba, 305-0044, Japan, National Institute of Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan, National Institute for Material Science (Japan), Physics, NIMS, National Institute of Materials Science, Japan, National Institute of Materials Science (NIMS), National Institute of Materials Science, Tsukuba, Ibaraki 305-0044, Japan, NIMS - Tsukuba

  • Jiaqiang Yan

    Materials Science and Engineering, The University of Tennessee, Oak Ridge National Lab, Oak Ridge National Laboratory, Materials Science and Technology Division, Oak Ridge National Laboratory, Materials Science and Technology Division, Oak Ridge National Lab, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA

  • David Mandrus

    Physics, University of Tennessee, Materials Science and Engineering, The University of Tennessee, Department of Materials Science & Engineering, University of Tennessee, Knoxville, The University of Tennesse, Knoxville, University of Tennessee, Department of Physics and Astronomy, University of Tennessee, Oak Ridge National Laboratory, Department of Materials Science and Engineering, University of Tennessee Knoxville, Department of Materials Science and Engineering, University of Tennessee, University of Tennessee, Knoxville, Material Science and Technology Division, Oak Ridge National Laboratory, Material Science and Technology Division, Oak Ridge National Lab

  • Hongyi Yu

    Sun Yat-Sen University (Zhuhai Campus), The University of Hong Kong, University of Hong Kong

  • Hanan Dery

    University of Rochester

  • Wang Yao

    University of Hong Kong, The University of Hong Kong, Department of Physics and Centre of Theoretical and Computational Physics, University of Hong Kong, Hong Kong, China

  • Xiaodong Xu

    University of Washington, Physics, University of Washington