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arXiv · 2207.07592

Spin-split collinear antiferromagnets: a large-scale ab-initio study

Yaqian Guo·Hui Liu·Oleg Janson·Ion Cosma Fulga·Jeroen van den Brink·Jorge I. Facio
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Abstract

It was recently discovered that, depending on their symmetries, collinear antiferromagnets can actually break the spin degeneracy in momentum space, even in the absence of spin-orbit coupling. Such systems, recently dubbed altermagnets, are signalled by the emergence of a spin-momentum texture set mainly by the crystal and magnetic structure, relativistic effects playing a secondary role. Here we consider all collinear $q$=0 antiferromagnetic compounds in the MAGNDATA database allowing for spin-split bands. Based on density-functional calculations for the experimentally reported crystal and magnetic structures, we study more than sixty compounds and introduce numerical measures for the average momentum-space spin splitting. We highlight some compounds that are of particular interest, either due to a relatively large spin splitting, such as CoF$_2$ and FeSO$_4$F, or because of their low-energy electronic structure. The latter include LiFe$_2$F$_6$, which hosts nearly flat spin-split bands next to the Fermi energy, as well as RuO$_2$, CrNb$_4$S$_8$, and CrSb, which are spin-split antiferromagnetic metals.

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Yaqian Guo, Hui Liu, Oleg Janson, Ion Cosma Fulga, Jeroen van den Brink, Jorge I. Facio. 2022-07-15. Spin-split collinear antiferromagnets: a large-scale ab-initio study. https://doi.org/10.1016/j.mtphys.2023.100991

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