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arXiv · 2611.04188

Orbital Hall effect from the Wannier function approach

Tapesh Gautam·S. Satpathy
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Abstract

Using the Wannier function approach, we develop a gauge-covariant formalism for the orbital angular momentum (OAM) operator and the orbital Hall conductivity (OHC). The Wannier function formulation resolves the position-operator ambiguity inherent to Bloch states, providing a transparent and rigorous theory of orbital transport. Our formalism is validated through a finite-lattice calculation of the Haldane model, where the OAM operator is evaluated exactly from its real-space definition. Our results are also relevant to other orbital phenomena in solids such as the orbital Edelstein effect, orbital torque generation, and the like, where the OAM plays a crucial role.

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Tapesh Gautam, S. Satpathy. 2026-11-03. Orbital Hall effect from the Wannier function approach. https://doi.org/10.1103/pd3s-q2z7

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