Zeeman spin-orbit coupling in antiferromagnetic conductors

Revaz Ramazashvili

doi:10.1016/j.jpcs.2018.09.033

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arXiv · 1810.03720

Zeeman spin-orbit coupling in antiferromagnetic conductors

Revaz Ramazashvili

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Abstract

This article is a brief review of Zeeman spin-orbit coupling, arising in a low-carrier commensurate Néel antiferromagnet subject to magnetic field. The field tends to lift the degeneracy of the electron spectrum. However, a hidden symmetry protects double degeneracy of Bloch eigenstates at special momenta in the Brillouin zone. The effective transverse $g$-factor vanishes at such points, thus acquiring a substantial momentum dependence, which turns a textbook Zeeman term into a spin-orbit coupling. After describing the symmetry underpinnings of the Zeeman spin-orbit coupling, I compare it with its intrinsic counterparts such as Rashba coupling, and then show how Zeeman spin-orbit coupling may survive in the presence of intrinsic spin-orbit coupling. Finally, I outline some of the likely experimental manifestations of Zeeman spin-orbit coupling, and compare it with similar phenomena in other settings such as semiconducting quantum wells.

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Revaz Ramazashvili. 2018-10-08. Zeeman spin-orbit coupling in antiferromagnetic conductors. https://doi.org/10.1016/j.jpcs.2018.09.033

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