Induced Anisotropy, Reorientation Transitions, and Domains in Magnetic Films and Multilayers

Abstract

We introduce a phenomenological theory which gives a consistent method to calculate the distribution of induced anisotropy and the equilibrium magnetization within a magnetic layer as functions of the layer thickness, the material parameters and applied magnetic field. Within this theory the transition from the in-plane phase (larger thickness) to the perpendicular phase (thinner films) always occurs continuously via transformation into an intermediary (twisted) phase which is inhomogeneous across the layer thickness. The complex redistribution of the magnetization in the twisted phase accounts for the peculiarities of domain structures in the transitional regions of layered systems such as Cu/Ni/Cu(001) and Co/Au(111).