EXCHANGE COUPLING COEFFICIENT AND DOMAIN-WALL MOBILITY OF (DY,TB)FECOMAGNETOOPTICAL FILMS

The magnetic properties and recording characteristics of (Dy,Tb)Fr,Co films are dependent upon the anisotropy dispersion of rare earth const ituents and the exchange integral between rare earth and transition me tal sub networks. The exchange coupling coefficient lambda and the dom ain wall mobility mu(eff) are found to be interrelated by both measure ments and calculations. The higher the lambda or the lower the mu(eff) , the higher bias field that is required for magneto-optical recording . The temperature independent lambda is demonstrated to be an importan t parameter in the assessment of magnetic properties and recording cha racteristics of sperimagnetic films. (C) 1997 American Institute of Ph ysics.