Nonlinear dynamics of topological ferromagnetic textures for frequency multiplication

Abstract: We propose that the non-linear radio-frequency dynamics and nanoscale size of topological magnetic structures associated to their well-defined internal modes advocate for their use as in-materio scalable frequency multipliers for spintronic systems. Frequency multipliers allow for frequency conversion between input and output frequencies, and thereby significantly increase the range of controllably accessible frequencies. In particular, we explore the excitation of eigenmodes of topological magnetic textures by fractions of the corresponding eigenfrequencies. We show via micromagnetic simulations that low-frequency perturbations to the system can efficiently excite bounded modes with a higher amplitude. For example, we excited the eigenmodes of isolated ferromagnetic skyrmions by applying half, a third and a quarter of the corresponding eigenfrequency. We predict that the frequency multiplication via magnetic structures is a general phenomenon which is independent of the particular properties of the magnetic texture, and works also for magnetic vortices, droplets and other topological textures.