Spatial coherence of interlayer excitons in 2D semiconductor heterostructures

ORAL

Abstract

MoSe2-WSe2 semiconductor heterostructures host long lived interlayer excitons (IXs) that emit light in the near infrared. The IXs in such heterostructures are composite bosons which, with the introduction of a bilayer h-BN separator, exhibit long range exciton flow. Numerous theoretical works have predicted these IXs can form a superfluid at low temperatures, motivating spatial coherence measurements. We performed optical coherence measurements on interlayer excitons in an h-BN separated MoSe2-WSe2 heterostructure. Specifically, we measured the spatial dependence of the degree of coherence present in the light emitted by IXs and observed long range (several micron) spatial coherence. The spatial coherence length of the MoSe2-hBN-WSe2 IXs is compared to a direct contact MoSe2-WSe2 device, showing qualitatively different spatial structure.

*We acknowledge support from NSF Grant Nos. DMR-2003583, ECCS-2054572, and AFOSR Grant Nos. FA9550-20-1-0217, FA9550-22-1-0312, FA9550-22-1-0113.

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Presenters

  • Jacob Cutshall

    • University of Arizona

Authors

  • Jacob Cutshall

    • University of Arizona

  • Fateme Mahdikhany

    • University of Arizona

  • Anna Roche

    • University of Arizona

  • Daniel N Shanks

    • University of Arizona

  • Michael Koehler

    • University of Tennessee

  • David Mandrus

    • University of Tennessee

  • Takashi Taniguchi

    • Kyoto Univ
    • National Institute for Materials Science
    • Research Center for Materials Nanoarchitectonics
    • Research Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • National Institute for Materials Sciences
    • NIMS
    • International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science
    • International Center for Materials Nanoarchitectonics, NIMS, Japan
    • International Center for Materials Nanoarchitectonics, Tsukuba
    • National Institue for Materials Science
    • Kyoto University
    • National Institute of Materials Science
    • International Center for Materials Nanoarchitectonics and National Institute for Materials Science

  • Kenji Watanabe

    • National Institute for Materials Science
    • NIMS
    • Research Center for Electronic and Optical Materials, National Institute for Materials Science
    • Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
    • National Institute for Material Science

  • Brian J LeRoy

    • University of Arizona

  • John R Schaibley

    • University of Arizona