INPLANE UNIAXIAL ANISOTROPY, COERCIVITY, AND MAGNETIC AFTEREFFECT OF COZRDY AMORPHOUS FILMS

Amorphous alloy thin films of (Co95Zr5)100-xDyx with a well-defined in -plane uniaxial anisotropy K(u) were prepared by rf sputtering. The sa turation magnetization, K(u), and the coercive field were studied as a function of temperature and for the composition range 4 < x < 20. M(s ) could be fitted by the molecular-field model, K(u) interpreted by a single-ion anisotropy process, and H(c) by a model of Alben, Becker, a nd Chi [J. Appl. Phys. 49, 1653 (1978)]. At low temperatures ( T < 50 K) and for the whole concentration range a new type of aftereffect is observed, the main characteristic of which is described.