Collective modes and optical response in twisted WSe<sub>2</sub>

ORAL

Abstract

Over a range of twist angles, twisted WSe2 displays a superconducting region in proximity to a correlated state (likely an intervalley-coherent (IVC) antiferromagnet (AFM)). We study the particle-hole collective modes of different IVC and valley-polarized (VP) phases within the time-dependent Hartree-Fock approximation. We track the evolution of the collective-mode velocity and gaps as a function of twist angle and dielectric screening. Due to the strong magneto-electric coupling in the IVC-AFM phase, we find a sizable finite-q optical response generated by its spin waves, potentially accessible in near-field or on-chip THz spectroscopy.

*D.M.S. acknowledges support from the National Science Foundation (NSF) Materials Research Science and Engineering Centers (MRSEC) program through Columbia University under the  precision-Assembled Quantum Materials (PAQM) Grant No. DMR-2011738. The Flatiron Institute is a division of the Simons Foundation.

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Presenters

  • Daniel Muñoz-Segovia

    • Columbia University

Authors

  • Daniel Muñoz-Segovia

    • Columbia University

  • Raquel Queiroz

    • Department of Physics, Columbia University, New York, NY, USA
    • Columbia University

  • Andrew J Millis

    • Columbia University
    • Flatiron Institute, Columbia University