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.