Saturation of Ferrimagnetic Resonance with Parallel Pumping

Abstract

The microwave susceptibility for subsidiary ferrimagnetic resonance with parallel pumping is calculated from the saturation amplitude of the unstable spin waves. The limiting of these runaway magnons is caused by three, four, and higher number magnon interactions. These interactions can lead to a nonlinear (as well as the usual linear) relaxation rate, which can be evaluated using certain approximations. The main features of the results agree with experiment.