Long-time calculation of the thermal magnetization reversal using Metropolis Monte Carlo

Abstract

The standard Metropolis Monte Carlo is used to simulate thermal magnetization decay in ensemble of interacting and non-interacting particles. The fitting of demagnetization curves to simple Neel-Arrhenius model, using the volume distribution, suggests that in a non-interacting case one Monte Carlo step is proportional to a square root of time. The same dependence arises from the consideration of magnetic particle moving in the external potential according to Brownian dynamics. This constitutes the basis of the so-called Monte Carlo with quantified time step. The analytical calculations show that the method works reasonably in the case of small-to-intermediate size barriers and for a high anisotropy system. The application of the method to magnetic recording media reveals qualitatively the same dependence on the exchange parameter as obtained by kinetic Monte Carlo. © 2002 Elsevier Science B.V. All rights reserved.