Mechanisms of fast coherent magnetization inversion in ferronanomagnets

Abstract Magnetic nanoparticles have a wide range of potential applications. The fast magnetization inversion is the goal of magnetic recording and other data storage, logic and communication applications operating at GHz frequencies. Here, we present theoretical studies on mechanisms of fast coherent magnetization inversion in the system of ferromagnetic nanoparticles composed of molecules or clusters with high magnetic moments. The possibilities to accelerate magnetic relaxation are considered: the feedback field from a resonator, radiation friction and Landau-Lifshitz relaxation. Equations of motion for the interparticle dipole-dipole interactions are solved numerically and the role of these relaxation mechanisms has been examined. Radiation friction is shown to be an important factor at certain conditions.