Floquet spin-group theory for light-tailored spin splitting in collinear magnets
This work develops a Floquet spin-group theory to study how light can control spin splitting in collinear magnets. By combining static magnetic crystal symmetry with light's dynamical symmetry, researchers classified five distinct classes of spin splitting. This framework shows that by changing the light's properties, one can selectively switch between odd, even, and mixed-parity splittings.