Generation of Propagating Spin Waves from Edges of Magnetic Nanostructures Pumped by Uniform Microwave Magnetic Field

Abstract

Thin-film patterned magnetic nanostructures are widely employed within perceived magnonic device architectures to guide and/or manipulate spin waves for data processing and communication purposes. Here, using micromagnetic simulations, we explore how the internal magnetic field nonuniformity inherent to patterned magnetic nanostructures can also be exploited to create spin-wave sources. The spin-wave emission is achieved through the resonant excitation of finite-sized regions of increased effective magnetic field formed near the edges of patterned structures. The phenomenon is rather universal and could be used to generate magnetodipole, dipole-exchange, and exchange dominated spin waves. Depending on the frequency of excitation and parameters of the nanostructures, the emitted spin waves may form either highly directional spin-wave caustic beams or more regular plane spin waves.