In-situ study of dynamics of symmetry-breaking stacking boundaries in bilayer MoS<sub>2</sub>

ORAL

Abstract

Engineering symmetry in 2D materials has recently emerged as a promising way to achieve novel properties and functions. Here we report the in-situ integration of AA’ and AB stacked bilayer MoS2 with different inversion-symmetries by creating atomically sharp stacking boundaries between the differently stacked domains, via thermal stimulation and electron irradiation, inside an atomic-resolution scanning transmission electron microscope. The setup enables us to track the formation and atomic motion of the stacking boundaries in real time and with ultra-high resolution which enables in-depth analysis on the atomic structure at the boundaries. In conjunction with density functional theory calculations, we establish the dynamics of the boundary nucleation and expansion, and further identify metallic boundary states. Our approach provides a means to synthesize domain boundaries with intriguing transport properties, and opens up a new avenue for controlling valleytronics in nanoscale domains via real-time patterning of domains with different symmetry properties.

*This work was supported in part by the U.S. Department of Energy under Contract No. DE-AC02-05-CH11231, Program No. KC2207 and KCWF16; by the National Science Foundation, under Grant No. 1542741, DMR-1206512 and DMR-1508412.

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Presenters

  • Aiming Yan

    • Physics, University of California, Berkeley
    • Univ of California - Berkeley

Authors

  • Aiming Yan

    • Physics, University of California, Berkeley
    • Univ of California - Berkeley

  • Chin Shen Ong

    • Physics, University of California, Berkeley

  • Diana Qiu

    • Physics, University of California, Berkeley
    • Physics, Univ of California - Berkeley
    • Lawrence Berkeley National Lab and University of California - Berkeley

  • Colin Ophus

    • National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory
    • National Center for Electron Microscopy, Lawrence Berkeley National Laboratory
    • Lawrence Berkeley National Laboratory
    • Lawrence Berkeley Natl Lab

  • Jim Ciston

    • National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory

  • Christian Merino

    • Physics, University of California, Berkeley

  • Steven Louie

    • Physics, University of California, Berkeley
    • University of California, Berkeley
    • Physics, Univ of California - Berkeley
    • Univ of California - Berkeley
    • Physics, UC Berkeley
    • Physics Department, UC Berkeley and Lawrence Berkeley National Lab
    • Department of Physics, University of California at Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory
    • Department of Physics, University of California, Berkeley
    • Physics Department, University of California Berkeley and Lawrence Berkeley National Lab
    • Department of physics, University of California - Berkeley
    • Lawrence Berkeley National Lab and University of California - Berkeley
    • Materials Sciences Division, Lawrence Berkeley National Laboratory & Department of Physics, University of California at Berkeley
    • UC Berkeley and Lawrence Berkeley National Lab
    • Physics, University of California - Berkeley

  • Alex Zettl

    • Physics, University of California, Berkeley
    • Physics, Univ of California - Berkeley
    • Department of physics, University of California - Berkeley
    • Physics, University of California at Berkeley