It is demonstrated that the decay time of spin-wave modes existing in a magnetic insulator can be reduced or enhanced by injecting an in-plane dc current, Idc, in an adjacent normal metal with strong spin-orbit interaction. The demonstration rests upon the measurement of the ferromagnetic resonance linewidth as a function of Idc in a 5~μm diameter YIG(20nm){\textbar}Pt(7nm) disk using a magnetic resonance force microscope (MRFM). Complete compensation of the damping of the fundamental mode is obtained for a current density of ∼3⋅1011A.m−2, in agreement with theoretical predictions. At this critical threshold the MRFM detects a small change of static magnetization, a behavior consistent with the onset of an auto-oscillation regime.
@article{arxiv.1405.7415,
title = {Electronic control of the spin-wave damping in a magnetic insulator},
author = {A. Hamadeh and O. d Allivy Kelly and C. Hahn and H. Meley and R. Bernard and A. H. Molpeceres and V. V. Naletov and M. Viret and A. Anane and V. Cros and S. O. Demokritov and J. L. Prieto and M. Munoz and G. de Loubens and O. Klein},
journal= {arXiv preprint arXiv:1405.7415},
year = {2014}
}