Excitation Modes for Spin Waves in a Two‐Dimensional Magnetic Vortex Lattice

In the flux‐closure vortex state, nano‐ and micron‐sized magnetic platelets exhibit in‐plane curling magnetization and nanometer‐sized perpendicularly magnetized vortex cores (VCs). Possessing the simplest nontrivial configuration, these objects are of wide interest to micromagnetics and may provide novel paths for spintronics applications. Spin‐wave eigenmodes resulting from the magnetostatic interaction are present in vortex‐state structures at frequencies higher than the gyrotropic modes of the VC. The proficient understanding of spin waves is an important roadblock in the fabrication of magnonic devices. Using micromagnetic simulations, the spin‐wave modes of a 2D square magnetic vortex lattice in six different lattice configurations using a sinc‐function field applied in‐plane and perpendicular to the disk plane are studied. This study, therefore, provides an in‐depth and detailed study of the collective azimuthal and radial spin‐wave eigenfrequencies in a 2D lattice of magnetic vortices and may provide a new approach for creating a new type of magnonic crystal employing magnetic vortices arranged in a lattice.