Induced, local anisotropy and anisotropy dispersion in amorphous Co-Zr-rare earth thin films

When prepared under adequate conditions, rf sputtered amorphous (Co0.93Zr0.07)100-xTbx thin films are obtained with fairly uniform magnetic properties and with a very well defined in-plane uniaxial anisotropy Ku. These layers, in consequence, are particularly well adapted in order to investigate the overall effect of the random local anisotropy Kloc upon the micromagnetic properties of the films. The experimental data were obtained by the transverse biased Initial susceptibility and ferromagnetic resonance measurement. The value of Kloc was determined using the ripple theory. Kloc increases with increasing amount of Tb in the layers, which can be explained by the single-ion anisotropy mechanism