Magnetisation reversal and domain structure in thin magnetic films: theory and computer simulation

A model is introduced for the theoretical description of nanoscale magnetic films with high perpendicular anisotropy. In the model the magnetic film is described in terms of single domain magnetic grains, interacting via exchange as well as via dipolar forces. Additionally, the model contains anisotropy energy and a coupling to an external magnetic field. Disorder is taken into account in order to describe realistic domain and domain wall structures. Within this framework the dependence of the energy on the film thickness can be discussed. The influence of a finite temperature as well as the dynamics can be modeled by a Monte Carlo simulation. The results on the hysteresis loops, the domain configurations, and the dynamics during the reversal process are in good agreement with experimental findings