Giant momentum-dependent spin splitting in centrosymmetric low-Z antiferromagnets

The traditional bulk Rashba effect predicts spin–orbit coupling-induced wave-vector-dependent spin splitting between energy bands in nonmagnetic solids that lack spatial inversion symmetry. The authors show here how the violation of magnetic symmetry leads instead to a few prototypes of momentum-dependent spin splitting of energy bands that are induced by antiferromagnetism. This discovery broadens the spintronics playing field to include centrosymmetric compounds, even made of light elements with low spin–orbit coupling. Atomistic density functional calculations show that giant splitting above 200 meV is possible between top two valence bands. This work establishes the symmetry conditions and provides the early material predictions for what is now widely known as altermagnets.

Physical Review B 102, 014422 (2020) — Editors’ Suggestion · Featured in Physics