Dynamic susceptibility of skyrmion clusters in Co/Pt nanodots

Abstract

We study the dynamic susceptibility of skyrmion clusters in Co/Pt nanodots using micromagnetic simulations. For this, we investigate the dynamic response of the skyrmions to a small magnetic field pulse applied parallel to the dot axis. Skyrmions exhibit a main resonance peak associated with the skyrmions' breathing mode, which is closely linked to the average radius of the skyrmions. Furthermore, we find that non-trivial secondary modes appear when the cluster size increases. These results can be used as a detection and characterization mechanism for skyrmion lattices in confined systems.