Interlayer exciton flow in hBN separated MoSe<sub>2</sub>/WSe<sub>2</sub> heterostructures

ORAL

Abstract

Twisted layers of van der Waals materials have been studied intensely in recent years. These materials can be thinned down to one layer and vertically stacked on top of each other to realize heterostructures. By changing parameters such as strain, stacking, external fields, doping, and twist angle, the physical properties of these structures can be manipulated. In this work, we fabricated a device consisting of two transition metal dichalcogenide (TMD) semiconductors, MoSe2 and WSe2. By stacking these layers on top of one another, the interaction between layers can form a periodic superlattice potential, known as a moiré potential. Upon optical excitation of MoSe2/WSe2 heterostructure, indirect interlayer excitons (IXs) form, which comprise an electron in the MoSe2 layer bound to a hole in WSe2 layer. The IX in this structure has several astonishing properties, including long lifetime and the permanent dipole moment. I will discuss our recent advances, separating the TMD layers using a bilayer hBN spacer layer which suppresses the moiré potential. I will discuss our recent measurements quantifying the flow of IXs in hBN separated heterostructures, which has been proposed as a promising platform for realizing high temperature superfluidity. Specifically, I will discuss the effects of temperature, doping, magnetic field and IX density on IX diffusion.

*We acknowledge funding from National Science Foundation, Grant Numbers: DMR-2003583 and ECCS-2054572

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Presenters

  • Fateme Mahdikhanysarvejahany

    • University of Arizona

Authors

  • Fateme Mahdikhanysarvejahany

    • University of Arizona

  • Daniel N Shanks

    • University of Arizona

  • Trevor Stanfill

    • University of Arizona

  • Michael Koehler

    • University of Tennessee
    • University of Tennessee, Knoxville

  • David G Mandrus

    • University of Tennessee
    • Oak Ridge National Laboratory

  • 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

  • Brian J LeRoy

    • University of Arizona

  • John R. Schaibley

    • University of Arizona