Delayed magnetic vortex core reversal

When switching the vortex core in a magnetic disc by a short excitation with an in-plane field, there is an initial global excitation of the magnetization due to a precession of the magnetization in the spatially homogeneous field. Then an energy transport from this global excitation towards the center of the disc takes place leading to a concentration of the energy close to the vortex core which suffices to switch the core. Because this transport requires time, there is a delay between the end of the excitation and the switching. This is demonstrated for switching by in-plane rotating GHz rf-bursts.