Valley properties of moiré-trapped Interlayer excitons in WSe<sub>2</sub>/WS<sub>2</sub> moiré superlattices

ORAL

Abstract

Moiré superlattices formed by stacking atomic layers of transition metal dichalcogenide semiconductors have emerged as a class of artificial photonic and electronic materials that can be engineered to realize fascinating many-body states. In this study, we investigate one- and two-exciton interlayer exciton states confined in the moiré potential of WSe2/WS2 twisted bilayers and investigate their spin-valley behavior. The interrogations of the valley-dependent selection rule and excitonic g factor distinguish excitons from different atomic registries within the superlattice. Valley polarization of the single exciton sites is found to be highly sensitive to optical excitation power and weak external magnetic field. These observations reflect the intriguing interplay between the singly and doubly occupied exciton sites, as well as the role of exchange interactions for moiré excitons. Our work provides insights into exciton relaxation and formation within moiré superlattices, offering a pathway to engineering quantum optoelectronic platforms with such systems.

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Presenters

  • YUEH-CHUN WU

    • University of Massachusetts Amherst

Authors

  • YUEH-CHUN WU

    • University of Massachusetts Amherst

  • Matthew DeCapua

    • University of Massachusetts Amherst

  • 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

  • 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

  • Jun Yan

    • University of Massachusetts Amherst