Magnetic studies of amorphous CoZrGdDy films with perpendicular and in-plane uniaxial anisotropy

Amorphous Co73±x±yZr5Gd14±xDy8±y thin films with x≈2 and y≈1 were prepared by rf sputtering in the presence of a dc field applied along the film plane. The films exhibit a perpendicular Hp and an in-plane Hu anisotropy related to the clusters formed around Gd and Dy, respectively. Here Hp>4πMs, while the respective values of 4πMs and Hu, so the magnetic properties changed with composition. The behavior of the stripe domains is classical for 4πMs>Hu, but affected by Hu for 4πMs∼Hu. When Hu>4πMs perpendicular domains sensitive to high perpendicular fields and in-plane domains to low ones are observed.