Loss separation for dynamic hysteresis in magnetic thin films

We show that the properties of dynamic hysteresis in ferromagnetic thin films can be explained in terms of the theory of loss separation. Remarkably, this theory, that was originally derived for bulk metallic materials, is applicable to disordered magnetic systems under fairly general conditions regardless of the particular damping mechanism. This is confirmed by numerical simulations of a driven random-field Ising model. We re-examine several experimental data reported in the literature on dynamic hysteresis in thin films and find that all of them find a natural interpretation in terms of loss separation, reconciling the apparent lack of universality observed in different materials. (C) 2007 Elsevier B.V. All rights reserved.