Local Characterization of Correlated States in an MoTe<sub>2</sub> Twisted Bilayer Moiré Superlattice

ORAL

Abstract

Moiré superlattices in transition metal dichalcogenides (TMDs) host a variety of exotic quantum phenomena, such as generalized Wigner crystals, the integer quantum anomalous Hall (QAH) effect, and fractional Chern insulators (FCIs). These topological and correlated phenomena are often accompanied by electronic states having novel signatures at the moiré length-scale that are difficult to probe with conventional optical or transport methods. We have used scanning tunneling microscopy/spectroscopy (STM/S) to examine the local electronic states in gate-tunable twisted MoTe2 (t-MoTe2) devices. Our samples include a Si/SiO2 back gate under the t-MoTe2 and a monolayer graphene/ hBN sensing layer above the t-MoTe2 that allow us to separately control the carrier density and electric field in the t-MoTe2 [1] and to detect the formation of insulating states in t-MoTe2 through charging/discharging events in the graphene sensing layer [2]. We have performed spectroscopic characterization of t-MoTe2 at different filling levels and electric fields to locally probe novel correlated and topological states observed previously in optical and transport measurements.

[1] H. Li et al., Nature 597, 650 (2021).

[2] H. Li et al., ArXiv: 2209.12830 (2022).

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Presenters

  • Aining Hu

    • University of California, Berkeley

Authors

  • Aining Hu

    • University of California, Berkeley

  • Dhanvanth Balakrishnan

    • University of California, Berkeley

  • Tiancong Zhu

    • University of California, Berkeley

  • Yi-Fan Zhao

    • University of California, Berkeley

  • 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

  • Alex K Zettl

    • University of California, Berkeley

  • Feng Wang

    • University of California, Berkeley & LBNL
    • University of California, Berkeley

  • Michael F Crommie

    • University of California, Berkeley