The influence of diameter on the magnetic saturation in Fe84Cu16/MgO [001] multilayered islands

Abstract The saturation field of circular islands, consisting of [ Fe 84 Cu 16 /MgO]9 Fe 84 Cu 16 multilayers, increases with decreasing diameter of the islands. When the diameter of the islands is below 450 nm the field induced changes are dominated by a coherent rotation of the moment of the Fe 84 Cu 16 layers. For diameters of 2 μ m and larger, a signature of domain nucleation and evolution is observed. The changes in the saturation field with diameter of the islands are ascribed to the interplay between interlayer exchange coupling, stray field coupling at the edges and the crystalline anisotropy of the Fe 84 Cu 16 layers.