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.
@article{arxiv.2311.12108,
title = {Intrinsic torque on the orbital angular momentum in an electric field},
author = {Rhonald Burgos Atencia and Daniel P. Arovas and Dimitrie Culcer},
journal= {arXiv preprint arXiv:2311.12108},
year = {2024}
}