Nonlinear Dynamics of Topological Ferromagnetic Textures for Frequency Multiplication

Abstract

We propose that the nonlinear radio-frequency dynamics and nanoscale size of topological magnetic structures associated with their well-defined internal modes advocate 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 bound modes with a higher amplitude. For example, we excite the eigenmodes of isolated ferromagnetic skyrmions by applying half, a third, and a quarter of the corresponding eigenfrequency. We predict that frequency multiplication via magnetic structures is a general phenomenon that is independent of the particular properties of the magnetic texture and works for magnetic vortices, droplets, and other topological textures.