Exchange coupling coefficient and domain wall mobility of (Dy,Tb)FeCo magneto-optical films

Abstract

The magnetic properties and recording characteristics of (Dy,Tb)FeCo films are dependent upon the anisotropy dispersion of rare earth constituents and the exchange integral between rare earth and transition metal sub networks. The exchange coupling coefficient λ and the domain wall mobility μeff are found to be interrelated by both measurements and calculations. The higher the λ or the lower the μeff, the higher bias field that is required for magneto-optical recording. The temperature independent λ is demonstrated to be an important parameter in the assessment of magnetic properties and recording characteristics of sperimagnetic films.