A computational model of thermally activated high speed magnetisation reversal in longitudinal thin film media

A computational model of thermally activated magnetisation reversal in long itudinal thin film recording media is described. We introduce thermal effec ts into the simulation by adding a random field term to the local field of each spin, thus converting the deterministic Landau-Lifshitz-Gilbert equati on of motion into the stochastic Langevin equation of the problem. The mode l includes anisotropic crystalline, magnetostatic (dipole), and exchange in teractions. Methods of perturbing and expanding a system of grains which in itially form a regular lattice has given a physically realistic system of g rains which lie on an isotropic physical structure having a log-normal grai n size distribution and also a random distribution of in plane easy axes. ( C) 1999 Elsevier Science B.V. All rights reserved.