The interface-induced magnetization damping of thin ferromagnetic films in contact with normal-metal layers is calculated from first principles for clean and disordered Fe/Au and Co/Cu interfaces. Interference effects arising from coherent scattering turn out to be very small, consistent with a very small magnetic coherence length. Because the mixing conductances which govern the spin transfer are to a good approximation real valued, the spin pumping can be described by an increased Gilbert damping factor but an unmodified gyromagnetic ratio. The results also confirm that the spin-current induced magnetization torque is an interface effect.
@article{arxiv.cond-mat/0402088,
title = {First-principles study of magnetization relaxation enhancement and spin-transfer in thin magnetic films},
author = {M. Zwierzycki and Y. Tserkovnyak and P. J. Kelly and A. Brataas and G. E. W. Bauer},
journal= {arXiv preprint arXiv:cond-mat/0402088},
year = {2009}
}
Comments
10 pages, 8 figures, RevTeX; modified according to Referees' requests