Anisotropy dispersion and ferromagnetic resonance of amorphous soft magnetic films.

Measurement of the anisotropy dispersion using ferromagnetic resonance at radio frequency has been reconsidered taking into account of the skin effect in relatively thick soft magnetic films. Numerical calculation for 1 μm thick amorphous films shows that the eddy current loss is comparable to the resonance absorption. The measured absorption for CoZr film is larger than the calculated one at low bias field, which suggests the eddy current anomaly. In CoZr/ SiO2 multilayered films, an anomaly is reduced. The frequency dependence of the loss part of the permeability is also discussed.