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Imaging the valley and orbital Hall effect in monolayer MoS2.

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. In this paper 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.

SUBMITTER: Xue F

PROVIDER: S-EPMC8201411 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Imaging the valley and orbital Hall effect in monolayer MoS<sub>2</sub>.

Xue Fei F Amin Vivek V Haney Paul M PM

Physical review. B 20200101 16

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. In this paper 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 ...[more]

PMID: 34131610

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