Preisach modeling of a magneto-optical medium with perpendicular magnetization

Magneto-optical Kerr effect measurements on a (0.3 nm Co/0.6 nm Pt)(15) multilayer film with perpendicular magnetization showed Kerr rotation hysteresis loops that are very square, but asymmetric: on the descending major loop, while the magnetization decreases rapidly once the applied field approaches the coercive field, there is a long tail as saturation is approached. Modeling of this behavior was performed using a Preisach-based approach. To account for the known changes in magnetization behavior as a function of the number of bilayers, the Preisach density function was replaced by the sum of as many Gaussian distributions as there were bilayers in the material. The parameters of these Gaussian functions were systematically varied. The resulting model shows a good fit to both the experimental major loop and a first-order reversal curve. (C) 1999 American Institute of Physics. [S0021-8979(99)23908-4].