Electrical Regulation of Transverse Spin Currents in Unconventional Magnetic Ferroeletrics

We identify hexagonal YMnO₃ as a material realization of the elusive β-phase of unconventional magnetism, a noncollinear antiferromagnetic state defined by intrinsic spin-momentum locking and a topological spin texture. First-principles calculations reveal that this unique electronic structure enables a perpendicular electric field to generate a transverse spin current, a response that occurs without requiring relativistic spin-orbit coupling. Symmetry analysis demonstrates that this spin current is intimately related to the material's ferroelectric polarization (P) that breaks the inversion symmetry and is rigorously forbidden at domain walls where P vanishes. This provides a blueprint for a non-volatile transistor where a gate voltage switches the spin current by controlling domain wall density, enabling all-electrical control for energy-efficient antiferromagnetic spintronics.