The domain wall spin torque-meter

TL;DR

This paper introduces a novel method for directly measuring the non-adiabatic spin-torque in domain walls, revealing a high ratio to the adiabatic component and implications for spintronic applications.

Contribution

The authors present a measurement technique that is independent of domain wall pinning and damping, providing new insights into the non-adiabatic spin-torque magnitude and its potential for enhanced device efficiency.

Findings

Non-adiabatic to adiabatic torque ratio can reach 1

High spin-flip rate explains the large non-adiabatic torque

Results suggest improved spin torque efficiency for applications

Abstract

We report the direct measurement of the non-adiabatic component of the spin-torque in domain walls. Our method is independent of both the pinning of the domain wall in the wire as well as of the Gilbert damping parameter. We demonstrate that the ratio between the non-adiabatic and the adiabatic components can be as high as 1, and explain this high value by the importance of the spin-flip rate to the non-adiabatic torque. Besides their fundamental significance these results open the way for applications by demonstrating a significant increase of the spin torque efficiency.