Abstract
Magnetic and magneto-optic properties were investigated for GdNd/FeCo multilayers prepared by means of RF magnetron sputtering. Adjusting the bilayer period as well as the composition of each layer, perpendicularly magnetized films with a square Kerr hysteresis loop were obtained. The perpendicular magnetic anisotropy increases with decreasing bilayer period. For a composition of 13 at% Co in FeCo layer, the anisotropy shows a maximum of 3×106 erg/cm3 at a bilayer period of 5Å. With increasing Co concentration up to 33 at%, the Curie temperature and the Kerr rotation increase, while the anisotropy shows a maximum at a composition of 10 at% Co. The Kerr rotation increases about 10% at a wavelength of 400 nm compared with GdNd/Fe multilayers. From these results, GdNd/FeCo multilayers are expected to be a candidate for magneto-optical recording media working with blue laser.
