RESUMO
By ion irradiation through a lithographically made resist mask, the magnetic properties of cobalt-platinum simple sandwiches and multilayers were patterned without affecting their roughness and optical properties. This was demonstrated on arrays of 1-micrometer lines by near- and far-field magnetooptical microscopy. The coercive force and magnetic anisotropy of the irradiated regions can be accurately controlled by the irradiation fluence. If combined with high-resolution lithography, this technique holds promise for ultrahigh-density magnetic recording applications.
RESUMO
The basic magnetic properties of three-dimensional nanostructured materials can be drastically different from those of a continuous film. High-resolution magnetic force microscopy studies of magnetic submicrometer-sized cobalt dots with geometrical dimensions comparable to the width of magnetic domains reveal a variety of intricate domain patterns controlled by the details of the dot geometry. By changing the thickness of the dots, the width of the geometrically constrained magnetic domains can be tuned. Concentric rings and spirals with vortex configurations have been stabilized, with particular incidence in the magnetization reversal process as observed in the ensemble-averaged hysteresis loops.
