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تسجيل مستخدم جديدImaging the valley and orbital Hall effect in monolayer MoS2
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The topological properties of a materials 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 MoS$_2$ can be used to measure its energy-dependent valley and orbital Hall conductivity.
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Gapped graphene has been proposed to be a good platform to observe the valley Hall effect, a transport phenomenon involving the flow of electrons that are characterized by different valley indices. In the present work, we show that this phenomenon is
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