Transmission of correlated electrons through sharp domain walls in magnetic nanowires: a renormalization group approach

TL;DR

This paper investigates how correlated electrons transmit through narrow domain walls in ferromagnetic nanowires, revealing that electron interactions significantly influence low-temperature conductance and can lead to large magnetoresistance effects.

Contribution

It introduces a renormalization group approach to analyze electron transmission through domain walls, highlighting the role of electron correlations in transport properties.

Findings

Electron correlations can suppress charge conductance at low temperatures.

Domain walls can produce large magnetoresistance in ballistic nanocontacts.

Spin current may persist even when charge transport is suppressed.

Abstract

The transmission of correlated electrons through a domain wall in a ferromagnetic one dimensional system is studied theoretically in the limit of a domain wall width smaller or comparable to the electron Fermi wavelength. The domain wall gives rise to both potential and spin dependent scattering of the charge carriers. Using a poor man's renormalization group approach for the electron-electron interactions, we obtain the low temperature behavior of the reflection and transmission coefficients. The results show that the low-temperature conductance is governed by the electron correlations, which may suppress charge transport without suppressing spin current. The results may account for a huge magnetoresistance associated with a domain wall in ballistic nanocontacs.