Imaging the valley and orbital Hall effect in monolayer MoS2

ORAL

Abstract

The topological properties of a material's electronic structure are encoded in its Berry curvature, a quantity which is intimately related to the transverse electrical conductivity. In transition metal dichalcogenides with broken inversion symmetry, the nonzero Berry curvature results in a valley Hall effect. We identify a previously unrecognized consequence of Berry curvature in these materials: an electric-field-induced change in the electrons' charge density orientation. We use first-principles calculations to show that measurements of the electric-field-induced change in the charge density or local density of states in MoS2 can be used to measure its energy-dependent valley and orbital Hall conductivity.

*F.X. acknowledges support under the Cooperative Research Agreement between the University of Maryland and the National Institute of Standards and Technology Physical Measurement Laboratory, Award No. 70NANB14H209, through the University of Maryland.

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Presenters

  • Paul M Haney

    • National Institute of Standards and Technology
    • Physical Measurement Laboratory, National Institute of Standards and Technology
    • Nanoscale Processes and Measurements Group, National Institute of Standards and Technology

Authors

  • Paul M Haney

    • National Institute of Standards and Technology
    • Physical Measurement Laboratory, National Institute of Standards and Technology
    • Nanoscale Processes and Measurements Group, National Institute of Standards and Technology

  • Vivek Amin

    • Dept. of Physics, Indiana University - Purdue University Indianapolis

  • Fei Xue

    • National Institute of Standards and Technology
    • Nanoscale Processes and Measurements Group, National Institute of Standards and Technology, Institute for Research in Electronics and Applied Physics & Maryland Nanocenter, U