Higher Order Resonances in Periodically Driven Magnon Systems

We analyze resonant excitations of ferromagnetic magnons via microwave pumping below the threshhold frequency using Floquet theory. A special feature of parameteric resonance is the possibility to create magnons with higher energy than the driving frequency, which allows for new tuning possibilities. We develop a theoretical framework that analytically predicts the region of resonances and resonance thresholds in thin films of ferro- and ferri-magnetic materials as a function of damping, amplitude and frequency. The results are compared with micomagnetic simulations.