MONTE CARLO SIMULATION OF THE RATE OF DOMAIN GROWTH IN MAGNETO-OPTIC MEDIA

抄録

  Monte Carlo simulations on a two-dimensional lattice of magnetic dipoles have been performed to investigate the rate of thermo-activated domain growth under a constant external field in thin magneto-optic films. The model considers two distinct energy barriers for domain nucleation and domain growth respectively. The nanoscale features in the domain wall motion are ignored. It is shown that during the growth process, the rate slows gradually as a result of the reduction in strength of the demagnetizing field and also may exhibit significant fluctuations if the domain structure is dendritic. For fixed domain size, the dependence on the applied field is found to be exponential v = v_oe^H/Ho, in agreement with experimental observation. The simulations also provide information on the demagnetizing and domain wall energy averaged over the domain boundary surface.