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arXiv · 2402.15616

Minimal Models for Altermagnetism

Mercè Roig·Andreas Kreisel·Yue Yu·Brian M. Andersen·Daniel F. Agterberg
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Abstract

Altermagnets feature vanishing net magnetization, like antiferromagnets, but exhibit time-reversal symmetry breaking and momentum-dependent spin-split band structures. Motivated by the prevalence of altermagnetic materials with non-symmorphic symmetry-dictated band degeneracies, we provide realistic minimal models for altermagnetism by constructing tight-binding models for nonsymmorphic space groups with a sublattice defined by two magnetic atoms. These models can be applied to monoclinic, orthorhombic, tetragonal, rhombohedral, hexagonal, and cubic materials and can describe d-wave, g-wave, and i-wave altermagnetism. By examining the altermagnetic susceptibility and mean field instabilities within a Hubbard model we reveal that these models have altermagnetic ground states and yield a Berry curvature that is linear in the spin-orbit coupling. We apply our models to RuO$_2$, MnF$_2$, FeSb$_2$, $\kappa$-Cl, CrSb, and MnTe.

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Mercè Roig, Andreas Kreisel, Yue Yu, Brian M. Andersen, Daniel F. Agterberg. 2024-02-23. Minimal Models for Altermagnetism. https://doi.org/10.1103/physrevb.110.144412

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