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arXiv · 2507.00982

Orbital Hall Effect and Angular Momentum Dynamics in Confined Geometries

Egor I. Kiselev·Benoît Douçot·Roderich Moessner
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Abstract

We present an analysis of the orbital Hall effect (OHE) in a strip geometry and derive a formula for the orbital angular momentum (OAM) accumulation at the edges. The result is expressed in terms of band structure parameters and scattering rates, providing a link between experimental observations of the OHE and the underlying microscopics. A key result is that the effective OAM decay rate follows a Dykonov-Perel-like scaling and is inversely proportional to the electron scattering rate, even if the latter is small. Furthermore, investigating OAM transport in an inhomogeneous setting, we show that non-Ohmic flows and spatially varying electric fields result in contributions to the OHE which are distinct from the well known intrinsic and extrinsic mechanisms.

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Egor I. Kiselev, Benoît Douçot, Roderich Moessner. 2025-07-01. Orbital Hall Effect and Angular Momentum Dynamics in Confined Geometries. https://arxiv.org/abs/2507.00982

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