Stochastic resonance in ferromagnetic domain motion

Abstract:

A model for the motion of a single ferromagnetic domain is studied numerically and analytically. A single strip in two dimensions and pinned at two inhomogeneities is considered. We suppose two stable configurations (positively or negatively curved with pinned ends) due to the action of a bistable potential. Further, it is assumed that the domain is driven externally by periodic and noisy magnetic fields. The noise makes the domain able to flip between the two configurations. The small temporally periodic fields synchronize these flippings and the phenomenon of stochastic resonance is observed. The signal to noise ratio of the output is investigated and shows a maximum for a nonvanishing intensity of the applied noise. Its dependency on the stiffness of the domain is studied.