Time-dependent coercivity in particulate recording media

In this paper, the time dependence of coercivity (Hc) in particulate systems in the thermal relaxation regime is calculated. The calculations were made for an aligned system of poly dispersed particles. In the thermal regime, the calculations show that the Brown's model for relaxation times gives better results than the Arrhenius-Neel model, due to the field dependence of the attempt frequency in the Brown's model