Gilbert and Landau-Lifshitz damping in the presense of spin-torque

TL;DR

This paper discusses the debate between Gilbert and Landau-Lifshitz damping forms in micromagnetics, emphasizing the role of spin-torque effects and providing arguments that favor Gilbert damping.

Contribution

The paper offers a new perspective supporting Gilbert damping over Landau-Lifshitz damping in the context of spin-torque phenomena.

Findings

Gilbert damping is favored in the presence of spin-torque effects.

Simple examples illustrate the advantages of Gilbert damping.

The debate clarifies the appropriate damping model in micromagnetic simulations.

Abstract

A recent article by Stiles et al. (cond-mat/0702020) argued in favor of the Landau-Lifshitz damping term in the micromagnetic equations of motion over that of the more commonly accepted Gilbert damping form. Much of their argument revolved around spin-torque driven domain wall motion in narrow magnetic wires, since the presence of spin-torques can more acutely draw a distinction between the two forms of damping. In this article, the author uses simple arguments and examples to offer an alternative point of view favoring Gilbert.