The study of magnetic permeability and magnetoimpedance: Effect of ferromagnetic alloy characteristics

The study of the magnetoimpedance effect (MI) in thin film multilayered structures was done by the finite element numerical simulation method (FEM). Longitudinal MI effect (external field and flowing current are parallel to each other) and transverse magnetic anisotropy were considered. The influence of saturation magnetization, anisotropy field, induced magnetic anisotropy peculiarities, electrical conductivity of permalloy layers in a multilayered structure placed in an external magnetic field under the influence of high-frequency alternating current was investigated. The highest sensitivity of the three-layered [FeNi]/Cu/[FeNi] structure was achieved at the maximum saturation magnetization, the smallest magnetic anisotropy field and the lowest dispersion of local effective anisotropy. Assumptions for further improving the model for prediction of the features of the frequency dependence of the MI ratio were discussed. FEM method was shown to be useful for design of MI elements with requested responses.