Path sampling for collapse rates of metastable magnetic skyrmions and direct comparison with transition state theory

L. Desplat, C. Vogler, J. -V. Kim, R. L. Stamps, D. Suess

Published 2019-05-10Version 1

We perform a direct comparison between transition state theory and forward flux sampling as a means to compute collapse rates of metastable magnetic skyrmions. We show that a good agreement is obtained between the two methods. We report variations of the attempt frequency by several orders of magnitude when the applied magnetic field varies weakly, which confirms the existence of a strong entropic contribution to the lifetime of skyrmions. This demonstrates that the knowledge of the rate prefactor, in addition to the internal energy barrier, is essential in order to properly estimate a lifetime.