Adiabatic Electron Dynamics in Antiferromagnetic Texture

TL;DR

This paper develops a theory for the adiabatic dynamics of conduction electrons in antiferromagnetic textures, revealing spin-dependent orbital motion influenced by emergent gauge fields, distinct from ferromagnetic systems.

Contribution

It introduces a novel framework for understanding electron dynamics in AFM textures, highlighting internal band dynamics and emergent gauge fields not present in FM systems.

Findings

Electron spins do not perfectly align with AFM background.

Orbital motion is spin-dependent and influenced by non-Abelian gauge fields.

Predictions for experimental observations are provided.

Abstract

Adiabatic dynamics of conduction electrons in antiferromagnetic (AFM) materials with slowly varying spin texture is developed. Quite different from the ferromagnetic (FM) case, adiabaticity in AFM texture does not imply perfect alignment of conduction electron spins with background profile, instead, it introduces an internal dynamics between degenerate bands. As a result, the orbital motion of conduction electrons becomes spin-dependent and is affected by two emergent gauge fields: one of them is the non-Abelian version of what has been discovered in FM systems; the other leads to an anomalous velocity that has no FM counterpart. Two examples with experimental predictions are provided.