Micromagnetic simulation of transverse biased initial susceptibility measurements

By means of the hybrid finite element-boundary element method (FEM-BEM) formulated by T.R. Koehler and D.R. Fredkin, we have simulated transverse biased initial susceptibility (TBIS) experiments in various thin film systems. We have varied system size, anisotropy constant, exchange constant and saturation magnetization value. According to the theory developed by Hoffmann, the TBIS measurements provide the values for two fields, the effective anisotropy field and the so-called dispersion field. In the present paper we explore the limits of the validity of TBIS experiments. Our simulations clearly show a good agreement between the anisotropy field obtained by means of the Hoffmann's theory (according to TBIS experiments) and the average anisotropy field for all studied systems. The relation of the Hoffmann's dispersion field with other different fields, calculated from the equilibrium moment configuration, as well as with microstructural characteristic features of the system has also been analysed. © 2001 Elsevier Science B.V.