Optical detection of electrostatically generated interlayer excitons

ORAL

Abstract

Interlayer excitons in transition metal dichalcogenide (TMD) heterostructures have been of great interest because of their potential to form a high temperature exciton condensate. Their large binding energies and long lifetimes allow interlayer excitons to exist within a large phase space of densities and temperatures. In a type-II band aligned MoSe2/hBN/WSe2 heterostructure, we electrostatically create interlayer excitons by independently controlling the charge densities in the electron and hole layers. The electron and hole densities in the exciton regime are calibrated by optical absorption in the uncorrelated regime. From the calibrated densities we observe a non-linear increase of the exciton density as a function of the bias voltage. Our observations can be qualitatively explained by a model consisting of permanent out-of-plane dipoles with a finite binding energy. The ability to create interlayer excitons in the electrostatic equilibrium limit lays the foundation towards systematically studying interlayer exciton transport in the condensate phase.

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Presenters

  • Andrew Joe

    • University of California Berkeley

Authors

  • Andrew Joe

    • University of California Berkeley

  • Ruishi Qi

    • University of California Berkeley

  • Tiancheng Zheng

    • University of California Berkeley

  • Zuocheng Zhang

    • University of California, Berkeley
    • University of California Berkeley

  • Jingxu Xie

    • uc berkeley

  • Emma Regan

    • University of California, Berkeley

  • Zheyu Lu

    • University of California Berkeley

  • Takashi Taniguchi

    • National Institute for Materials Science
    • Kyoto Univ
    • International Center for Materials Nanoarchitectonics, National Institute of Materials Science
    • Kyoto University
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-044, Japan
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • National Institute for Materials Science, Japan
    • National Institute For Materials Science
    • NIMS
    • National Institute for Material Science
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan
    • NIMS Japan

  • Kenji Watanabe

    • National Institute for Materials Science
    • Research Center for Functional Materials, National Institute of Materials Science
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-044, Japan
    • NIMS
    • Research Center for Functional Materials, National Institute for Materials Science
    • National Institute for Materials Science, Japan
    • Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Japan
    • NIMS Japan

  • Sefaattin Tongay

    • Arizona State University
    • FIAP

  • feng wang

    • University of California, Berkeley