INDUCED, LOCAL ANISOTROPY AND ANISOTROPY DISPERSION IN AMORPHOUS CO-ZR RARE-EARTH THIN-FILMS

When prepared under adequate conditions, rf sputtered amorphous (Co0.9 3Zr0.07)(100-x)Tb-x thin films are obtained with fairly uniform magnet ic properties and with a very well defined in-plane uniaxial anisotrop y K-u. These layers, in consequence, are particularly well adapted in order to investigate the overall effect of the random local anisotropy K-loc upon the micromagnetic properties of the films. The experimenta l data were obtained by the transverse biased initial susceptibility a nd ferromagnetic resonance measurement. The value of K-loc was determi ned using the ripple theory. K-loc increases with increasing amount of Tb in the layers, which can be explained by the single-ion anisotropy mechanism.