Intrinsic Nonlinear Spin Magnetoelectricity in Centrosymmetric Magnets

TL;DR

This paper introduces an intrinsic nonlinear spin magnetoelectric effect in centrosymmetric magnets, driven by band geometry, enabling all-electric control of spins and promising new spintronic device functionalities.

Contribution

It reveals the band geometric origin of nonlinear spin magnetoelectricity and predicts its sizable presence in single-layer MnBi₂Te₄ through first-principles calculations.

Findings

Intrinsic nonlinear spin magnetoelectric effect exists in centrosymmetric magnets.

The effect is determined by band structure and Berry connection polarizabilities.

Predicted sizable nonlinear response in single-layer MnBi₂Te₄.

Abstract

We propose an intrinsic nonlinear spin magnetoelectric effect in magnetic materials, offering the potential of all-electric control of spin degree of freedom in centrosymmetric magnets, which reside outside of the current paradigm based on linear spin response. We reveal the band geometric origin of this effect in the momentum and magnetization space Berry connection polarizabilities, and clarify its symmetry characters. As an intrinsic effect, it is determined solely by the material's band structure and represents a material characteristic. Combining our theory with first-principles calculations, we predict sizable nonlinear spin magnetoelectricity in single-layer MnBi$_{2}$Te$_{4}$, which can be detected in experiment. Our theory paves the way for exploring rich nonlinear spintronic effects and novel device concepts based on them.