Effect of material parameters on magnetization process in microstructured thin film

Effects of material parameters on the magnetization process in a sub-micron strip pattern have been studied by micromagnetic simulations. A grain structure in the thin film is modeled by a discretized square element array. A structural parameter is introduced considering discontinuous film structure. The exchange stiffness is also varied as parameters. Simulated transverse susceptibility χ and the longitudinal magnetization reversal field H_rev in continuous film structure are somewhat smaller than the analytical predictions based on the coherent rotation model. The values of χ and H_rev significantly decrease with the decrease of inter-grain coupling due to discontinuous structure. Numerical analysis for transients of the internal energy during the magnetization process reveals that the demagnetizing term dominates the transverse magnetization process. While, the demagnetizing and exchange energy terms comparatively contribute to the potential barrier for the longitudinal magnetization reversal. Various types of micromagnetic configurations of edge-curl, buckling and vortex were observed in the magnetization reversal depending on the material parameters.