Effect of electrical bias on spin transport across a magnetic domain wall

TL;DR

This paper develops a theoretical model showing how electrical bias influences spin transport across magnetic domain walls, affecting spin-flip rates and device performance, particularly in spin diodes.

Contribution

It introduces a theory linking electrical bias to spin-flip probability and domain wall width, enhancing understanding of spin transport control.

Findings

Increasing voltage reduces spin-flip rate

Bias widens the operational temperature window of spin diodes

Electrical bias effectively narrows the domain wall

Abstract

We present a theory of the current-voltage characteristics of a magnetic domain wall between two highly spin-polarized materials, which takes into account the effect of the electrical bias on the spin-flip probability of an electron crossing the wall. We show that increasing the voltage reduces the spin-flip rate, and is therefore equivalent to reducing the width of the domain wall. As an application, we show that this effect widens the temperature window in which the operation of a unipolar spin diode is nearly ideal.