High Power Ferromagnetic Resonance in Thin Permalloy Films - The Steady State Response, Threshold Modifications, and Magnon Scattering

摘要

Nonlinear magnetization dynamics in thin metallic ferromagnetic films plays an essential role in magnetic switching and spin torque transfer [1, 2]. Early high power ferromagnetic resonance (FMR) experiments on metal films [3, 4] provided a qualitative demonstration that Suhl spin wave instability processes [5] are operative in these systems. There has been a resurgence of interest in this area recently because of the relevance of Suhl processes to large angle switching dynamics and damping [1, 6]. Ref. 6, in particular, presents detailed data and analyses for the onset of Suhl instabilities in Permalloy thin films in the subsidiary absorption regime, for fields well below the FMR field region. For realistic large angle switching applications, however, it is more important to consider the role of Suhl processes in the FMR regime.