Threshold current for switching of a perpendicular magnetic layer induced by spin Hall effect

TL;DR

This paper provides an analytical model for the threshold current needed to switch a perpendicular magnetic layer via the spin Hall effect, revealing key dependencies and aiding device design.

Contribution

It introduces an analytic expression for the threshold switching current that matches numerical results and is useful for designing spin Hall effect-based magnetic devices.

Findings

Threshold current is independent of damping in high damping regime.

Threshold current is proportional to magnetic anisotropy and external in-plane field.

Analytic expression accurately predicts switching behavior.

Abstract

We theoretically investigate the switching of a perpendicular magnetic layer by in-plane charge current due to the spin Hall effect. We find that, in the high damping regime, the threshold switching current is independent of the damping constant, and is almost linearly proportional to both effective perpendicular magnetic anisotropy field and external in-plane field applied along the current direction. We obtain an analytic expression of the threshold current, in excellent agreement with numerical results. This expression can be used to determine the physical quantities associated with spin Hall effect, and to design relevant magnetic devices based on the switching of perpendicular magnetic layers.