Non-Newtonian dynamics of the fast motion of a magnetic vortex

Abstract

The dynamics of a magnetic vortex in a thin magnetically soft ferromagnetic disc with a submicron diameter has been analyzed. Under the action of field pulses with a duration of the order of 10–100 ps, the vortex undergoes a complex motion. The analysis of the results of a micromagnetic simulation indicates that this motion is non-Newtonian. It can be described by an equation containing the third time derivative of the displacement of the vortex core.