Quantitative measurement of layer-to-layer electronic coupling in bilayer MoS<sub>2</sub>

ORAL

Abstract

Interlayer electronic coupling plays a critical role in determining the electronic properties of van der Waal (vdW) bilayers. In particular, the coupling strength is dictated by the stacking configuration and the interlayer spacing. While the former has been well established, the influence of interlayer spacing still remains largely unexplored. Here, by measuring the optical transition of bilayer MoS2 in the diamond anvil cell, we quantitatively determined the interlayer coupling at various critical points of the Brillouin zone. The K-point coupling strength we obtained is ~40 meV, which can be increased to more than 100 meV at a reduced interlayer spacing of ~8%. In addition, the energy evolution of the indirect gap is used to measure the coupling strength of Q and Γ points. All experimental results are compared with the density functional theory. Our work has confirmed the great potential in tailoring vdW bilayers using compressive pressure.

*This research was supported by the Welch Foundation (F-1672), the US Airforce (FA2386-18-1-4097), and the US National Science Foundation (DMR-1808751 and the MRSEC program DMR-1720595).

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Presenters

  • Wei-Ting Hsu

    • Natl Tsing Hua Univ
    • University of Texas at Austin

Authors

  • Wei-Ting Hsu

    • Natl Tsing Hua Univ
    • University of Texas at Austin

  • Jiamin Quan

    • University of Texas at Austin
    • Department of Physics, The University of Texas at Austin
    • Department of Physics, Center of Complex Quantum Systems, University of Texas at Austin

  • Peng-Jen Chen

    • Inst of Physics Academia Sinica

  • Wen-Hao Chang

    • Department of Electrophysics, National Chiao Tung University
    • Electrophysics, National Chiao Tung University
    • Natl Chiao Tung Univ

  • Xiaoqin (Elaine) Li

    • University of Texas at Austin
    • Physics, University of Texas at Austin
    • Department of Physics, University of Texas at Austin
    • U.T. Austin
    • Department of Physics, The University of Texas at Austin
    • Department of Physics, Center of Complex Quantum Systems, University of Texas at Austin

  • Jung-Fu Lin

    • University of Texas at Austin

  • Chih-Kang Shih

    • Physics, University of Texas at Austin
    • University of Texas at Austin
    • Department of Physics, The University of Texas at Austin