Theory of Domain Wall Dynamics under Current

TL;DR

This paper reviews a microscopic theory of how domain walls move under electric current, focusing on spin-transfer torque, forces, and effects of spin relaxation, using a perturbative approach to non-adiabaticity.

Contribution

It provides a detailed microscopic derivation of domain wall dynamics considering non-adiabatic effects and spin relaxation, advancing understanding of current-induced domain wall motion.

Findings

Derived spin-transfer torque and forces on domain walls from $s$-$d$ exchange interaction.

Analyzed effects of non-adiabaticity using gauge field perturbation.

Studied impact of spin relaxation on domain wall dynamics.

Abstract

Microscopic theory of domain wall dynamics under electric current is reviewed. Domain wall is treated as rigid and planar. The spin-transfer torque and forces on the wall are derived based on the $s$-$d$ exchange interaction between localized spins and conduction electrons, treating non-adiabaticity expressed by the gauge field perturbatively. Effect of spin relaxation is also studied.