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) mul tilayer film with perpendicular magnetization showed Kerr rotation hysteres is loops that are very square, but asymmetric: on the descending major loop , while the magnetization decreases rapidly once the applied field approach es the coercive field, there is a long tail as saturation is approached. Mo deling of this behavior was performed using a Preisach-based approach. To a ccount 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. T he parameters of these Gaussian functions were systematically varied. The r esulting model shows a good fit to both the experimental major loop and a f irst-order reversal curve. (C) 1999 American Institute of Physics. [S0021-8 979(99)23908-4].