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arXiv · 2308.14878

Dominance of extrinsic scattering mechanisms in the orbital Hall effect: graphene, transition metal dichalcogenides and topological antiferromagnets

Hong Liu·Dimitrie Culcer
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Abstract

The theory of the orbital Hall effect (OHE), a transverse flow of orbital angular momentum in response to an electric field, has concentrated overwhelmingly on intrinsic mechanisms. Here, using a quantum kinetic formulation, we determine the full OHE in the presence of short-range disorder using 2D massive Dirac fermions as a prototype. We find that, in doped systems, extrinsic effects associated with the Fermi surface (skew scattering and side jump) provide $\approx 95\%$ of the OHE. This suggests that, at experimentally relevant transport densities, the OHE is primarily extrinsic.

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Hong Liu, Dimitrie Culcer. 2023-08-28. Dominance of extrinsic scattering mechanisms in the orbital Hall effect: graphene, transition metal dichalcogenides and topological antiferromagnets. https://doi.org/10.1103/physrevlett.132.186302

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