Magnetic Anisotropy Dispersion With Exchange Energy in Soft Ferromagnetic Thin Films

In ferromagnetic thin films, the effect of the magnetic anisotropy dispersion on the quasi-static susceptibility measured under a static magnetic field is shown. An approach is presented to estimate the anisotropy distribution both in angle and intensity from static and dynamical magnetic measurements. Because the transverse biased susceptibility is not fully described by the single anisotropy model, in particular for H approximate to H-K, either a full magnetic anisotropy dispersion P(phi, H-K) without exchange energy or a double anisotropy modeling coupled by the exchange energy are introduced to access the observed behavior. These two extreme magnetic configurations are discussed.