Micromagnetic modeling of ferromagnetic resonance assisted switching

We studied the steady state behavior and magnetization switching process of single domain particles subject to ac and dc magnetic fields using analytical and numerical models based on the Landau-Lifshitz-Gilbert equation. We compared the analytical solutions for circularly polarized fields with a numerical single spin model and circularly and linearly polarized ac magnetic fields. It has been found, that the initial conditions and the dynamics of the external fields (field ramps and amplitude changes) strongly determine which precession orbit the magnetization converges to, if the magnetization precession is stable, and if the magnetization switches. We also studied the effects of field amplitudes, field angles, and damping on the switching behavior. The presented results can be applied to high power ferromagnetic resonance experiments and ferromagnetic resonance assisted magnetic recording schemes.