Energetic framework for the description of temperature dependent magnetization in ferromagnetic thin films

Starting from a statistical description of the macroscopic magnetization process in the framework of an energetic model, a temperature dependence of the spontaneous magnetization can be derived. For thin film material and in-plane magnetization it is sufficient to deal with a 2-dimensional formulation of the model. So the orientation of elementary magnetic dipoles is represented by statistical distribution functions for the angle of the magnetic moments. Local energy terms as well as internal entropy that can be related to the differential entropy of the angular distribution determine the grade of alignment of the elementary entities. The results are compared to established theories and experimental findings from corresponding literature. Finally, the presented work should reveal how temperature dependence can be included into macroscopic hysteresis models endogenously, based on first principles calculations.