Stepwise behavior of the core trajectory in magnetic vortex dynamics under an alternating-current magnetic field

Abstract

We predict that the radial distance of a magnetic vortex core from the disk center shows a stepwise behavior during initial excited motion under an alternating-current magnetic field by means of micromagnetic simulations. The stepwise behavior is clearly observed around the resonance frequency and depends on the amplitude and frequency of the external magnetic field. It has been found that the stepwise behavior originates from the relative phase difference between the gyrovector and the radial distance of the vortex core. (C) 2013 AIP Publishing LLC.