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arXiv · 0805.0378

Kramers degeneracy in a magnetic field and Zeeman spin-orbit coupling in antiferromagnetic conductors

Revaz Ramazashvili
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Abstract

In this article, I study magnetic response of electron wavefunctions in a commensurate collinear antiferromagnet. I show that, at a special set of momenta, hidden anti-unitary symmetry protects Kramers degeneracy of Bloch eigenstates against a magnetic field, pointing transversely to staggered magnetization. Hence a substantial momentum dependence of the transverse g-factor in the Zeeman term, turning the latter into a spin-orbit coupling, that may be present in materials from chromium to borocarbides, cuprates, pnictides, as well as organic and heavy fermion conductors.

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Revaz Ramazashvili. 2008-09-24. Kramers degeneracy in a magnetic field and Zeeman spin-orbit coupling in antiferromagnetic conductors. https://doi.org/10.1103/physrevlett.101.137202

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