Electrical Regulation of Transverse Spin Currents in Unconventional Magnetic Ferroeletrics

TL;DR

This paper demonstrates that hexagonal YMnO$_3$ exhibits a unique electronic structure allowing electric-field-induced transverse spin currents without spin-orbit coupling, enabling energy-efficient antiferromagnetic spintronics.

Contribution

It identifies a new magnetic phase in YMnO$_3$ with intrinsic spin-momentum locking and proposes a novel electric control mechanism for spin currents in antiferromagnetic materials.

Findings

Electric field generates transverse spin currents in YMnO$_3$

Spin current is linked to ferroelectric polarization

Domain walls suppress spin current response

Abstract

We identify hexagonal YMnO$_3$ as a material realization of the elusive $\beta$-phase of unconventional magnetism, a noncollinear, noncoplanar antiferromagnetic state defined by intrinsic spin-momentum locking and a topological spin texture. First-principle calculations reveal that this unique electronic structure enables a perpendicular electric field to generate a transverse pure 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 that breaks the inversion symmetry and is rigorously forbidden at domain walls where electrical polarization vanishes. This provides a blueprint for a non-volatile transistor where a gate voltage switches the spin current conductivity by controlling domain wall density, enabling all-electrical control for energy-efficient antiferromagnetic spintronics.