Matching domain wall configuration and spin-orbit torques for very efficient domain-wall motion

TL;DR

This paper numerically identifies optimal conditions for highly efficient domain wall motion driven by spin-orbit torques, emphasizing the importance of configuration, injection scheme, and symmetry for maximizing velocity.

Contribution

It reveals the critical dependence of domain wall motion efficiency on configuration and symmetry, proposing a Ne9el wall driven by spin Hall effect as optimal.

Findings

Ne9el wall driven by spin Hall effect achieves up to 10 times higher velocity

Efficiency depends critically on domain wall configuration and symmetry

Optimal conditions significantly outperform conventional spin-transfer torque

Abstract

In our numerical study, we identify the best conditions for efficient domain wall motion by spin-orbit torques originating from the Spin Hall effect or Rashba effect. We demonstrate that the effect depends critically on the domain wall configuration, the current injection scheme and the symmetry of the spin-orbit torque. The best identified configuration corresponds to a N\'eel wall driven by spin Hall Effect in a narrow strip with perpendicular magnetic anisotropy. In this case, the domain wall velocity can be a factor of 10 larger than that for the conventional current-in-plane spin-transfer torque.