Permeability and anisotropy dispersion of amorphous soft magnetic films.

Abstract

Frequency dependence of permeability has been calculated for soft magnetic thin films which have amplitude and angular dispersion of the uniaxial anisotropy. The calculation has been adopted for amorphous Co-Nb films whose anisotropy dispersion has been determined by low frequency FMR measurements. Comparison of the measured permeability with the calculation suggests that the effective uniaxial anisotropy is dispersed more widely with low values than that obtained by the FMR method. The magnetization ripple is deduced to be one of the origins of the low effective field.