A Charge Density Wave Activated Exciton in TiSe<sub>2</sub>-MoSe<sub>2</sub> Heterostructures

ORAL

Abstract

Van der Waals heterostructures allow for the exploration of interface physics without the constraint of lattice matching. In this study we examine proximity effects in a vdW heterostructure comprised of TiSe2 and monolayer MoSe2. Using temperature-dependent, spatially-resolved photoluminescence (PL) microscopy we discover a new MoSe2 PL emission line at the TiSe2-MoSe2 interface. This PL line appears 30 meV above the MoSe2 neutral exciton which excludes localized or trapped excitons as a viable explanation. Temperature-dependent measurements show a surprising correlation of the high energy PL line with the TiSe2 CDW state, thus suggesting the CDW plays a central role in activating this previously unobserved exciton. We discuss possible CDW-based origins of this feature and outline future opportunities for using proximity effects in vdW heterostructures to engineer novel excitonic states.

*Co-authors acknowledge support from the National Science Foundation under DMR-1748650 and DMR-1847782; the US DOE, Office of Science BES under Award No.DE-SC0004890; and the Gordon and Betty Moore Foundation's EPiQS Initiative through Grant No. GBMF9071.

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Presenters

  • Patrick M Vora

    • George Mason University
    • Quantum Science and Engineering Center, Department of Physics and Astronomy - George Mason University

Authors

  • Jaydeep Joshi

    • Quantum Science and Engineering Center, Department of Physics and Astronomy - George Mason University
    • George Mason University

  • Benedikt Scharf

    • Julius-Maximilians University of Wuerzburg

  • Igor Mazin

    • George Mason University
    • Department of Physics and Astronomy and Quantum Science and Engineering Center, George Mason University, Fairfax, Virginia 22030, USA
    • Quantum Science and Engineering Center, Department of Physics and Astronomy - George Mason University

  • Sergiy Krylyuk

    • National Institute of Standards and Technology

  • Daniel J Campbell

    • University of Maryland, College Park

  • Johnpierre Paglione

    • University of Maryland, College Park
    • Maryland Quantum Materials Center, University of Maryland, College Park, MD 20742, USA
    • Univ of Maryland-College Park

  • Albert Davydov

    • Materials Science and Engineering Division, National Institute of Science and Technology
    • National Institute of Standards and Technology
    • Materials Science and Engineering Division - National Institute of Standards and Technology

  • Igor Zutic

    • State Univ of NY - Buffalo

  • Patrick M Vora

    • George Mason University
    • Quantum Science and Engineering Center, Department of Physics and Astronomy - George Mason University