Quadrupolar-dipolar excitonic transition in a tunnel-coupled van der Waals heterotrilayer

ORAL

Abstract

Strongly bound excitons determine light-matter interactions in van der Waals (vdW) heterostructures of two-dimensional semiconductors. Unlike fundamental particles, quasiparticles in condensed matter, such as excitons, can be tailored to alter their interactions and realize emergent quantum phases. Here, using a WS2/WSe2/WS2 heterotrilayer, we create a quantum superposition of oppositely oriented dipolar excitons – a quadrupolar exciton – wherein an electron is layer-hybridized in WS2 layers while the hole localizes in WSe2. In contrast to dipolar excitons, symmetric quadrupolar excitons only redshift in an out-of-plane electric field. At higher densities and finite electric field, the nonlinear Stark shift of quadrupolar excitons becomes linear, signalling a transition to dipolar excitons resulting from exciton-exciton interactions, while at vanishing electric field, reduced exchange interaction suggests antiferroelectric correlations between dipolar excitons. Our results present vdW heterotrilayers as a field-tunable platform to engineer light-matter interactions and explore quantum phase transitions between spontaneously ordered many-exciton phases.

*EFMA-1741691NSF-1905809SERI-101043957ERC-2015-AdG694097

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Presenters

  • Zach J Hadjri

    • Emory University

Authors

  • Zach J Hadjri

    • Emory University

  • Weijie Li

    • University of Washington

  • Luka Matej Devenica

    • Emory University

  • Jin Zhang

    • Max Planck Institute for Plasma Physics

  • Song Liu

    • Columbia University

  • James C Hone

    • Columbia University

  • 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

  • Angel Rubio

    • Max Planck Institute for the Structure & Dynamics of Matter
    • Max Planck Institute for the Structure and Dynamics of Matter
    • Max Planck Institute for the Structure &
    • Max Planck Institute for the Structure & Dynamics of Matter; Center for Computational Quantum Physics, Flatiron Institute
    • Center for Computational Quantum Physics, Flatiron Institute
    • Max Planck Institute for the Structure and Dynamics of Matter - Flatiron Institute
    • Max Planck Institute for Structure and Dynamics of Matter

  • Ajit Srivastava

    • Emory University