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arXiv · 2311.12108

Intrinsic torque on the orbital angular momentum in an electric field

Rhonald Burgos Atencia·Daniel P. Arovas·Dimitrie Culcer
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Abstract

Orbitronics harnesses non-equilibrium densities and flows of electrons orbital angular momentum (OAM). Although the OAM must be long lived to be useful in information processing, the mechanisms leading to OAM non-conservation remain unknown. Here we show that an electric field induces an intrinsic torque on the OAM mediated by the quantum metric tensor, without spin-orbit coupling or magnetic fields. The torque vanishes in pseudospin-1/2 systems with particle-hole symmetry but is nonzero in the presence of nontrivial textures. We discuss implications for topological materials and strategies for experimental observation.

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Rhonald Burgos Atencia, Daniel P. Arovas, Dimitrie Culcer. 2023-11-20. Intrinsic torque on the orbital angular momentum in an electric field. https://doi.org/10.1103/physrevb.110.035427

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