Nonrelativistic Spin-Orbit-Coupling Effects in Odd-Parity Coplanar Magnets

Abstract: Spin-orbit coupling (SOC) is a relativistic effect that underpins a broad spectrum of phenomena in condensed matter physics, from topological phases of matter to spintronic functionality. Its relativistic origin, however, restricts strong SOC to heavy-element materials and locks spin-momentum texture into a fixed, material-specific pattern. Here we show that odd-parity coplanar magnets offer a nonrelativistic pathway to highly tunable SOC effects. We construct a bilayer coplanar magnet via symmetry-guided stacking of two monolayer odd-parity altermagnets and demonstrate that Rashba, Weyl, and Dresselhaus spin textures can all be realized, and that the spin texture can be switched between these forms simply by tuning the layer Neel vector. Through the spin Edelstein effect and the realization of fully gapped chiral topological superconducting phases, we demonstrate that this nonrelativistic SOC achieves physical equivalence to its relativistic counterpart. Our findings identify a new class of odd-parity coplanar magnets as a versatile platform for engineering SOC effects.