Domain wall size and magnetic losses in frequency spectra of ferrites and garnets

It is shown that the value and the frequency of losses in susceptibility spectra follow the relation established by Globus : the value of μ" is proportional to the mean grain size Dm, the relaxation frequency is proportional to . Curves obtained from series of NiFe2O4and YIG samples with various Dmare reduced to single curves. It has been also possible, by taking into account the specific properties (the spontaneous magnetization, the total and magnetocrystalline anisotropy fields) to reduce the final single curves for both the compositions to a single intercomposition curve of losses as a function of frequency.