Role of electron correlations in transport through domain walls in magnetic nanowires

TL;DR

This paper investigates how electron correlations affect electron transport through magnetic domain walls in nanowires, revealing that strong interactions can lead to complete reflection and spin current generation without charge flow.

Contribution

It introduces a theoretical analysis using renormalization group methods to understand electron scattering and spin transport in correlated ferromagnetic nanowires with domain walls.

Findings

Repulsive interactions cause total electron reflection at zero temperature.

Domain walls can flip electron spins, producing spin currents without charge currents.

The study provides scaling equations for scattering amplitudes in correlated systems.

Abstract

The transmission of correlated electrons through a domain wall in ferromagnetic quasi-one-dimensional systems is studied theoretically in the case when the domain wall width is comparable with the Fermi wavelength of the charge carriers. The wall gives rise to both potential and spin dependent scattering. Using a poor man's renormalization group approach, we obtain scaling equations for the scattering amplitudes. For repulsive interactions, the wall is shown to reflect all incident electrons at the zero temperature fixed points. In one of the fixed points the wall additionally flips the spin of all incident electrons, generating a finite spin current without associated charge current.