Theoretical estimation of magnetoimpedance frequency dependence in amorphous wires

Abstract This paper concerns about the theoretical estimation of the magnetoimpedance (MI) ratio frequency dependence. Special attention is paid in reproducing the frequency dependence of the maximum MI ratios achieved experimentally. In order to reproduce qualitatively experimental data, several aspects should be taken into account. The first one is that the samples are not completely saturated in the recent experiments, leading to a decrease of the MI that can be enough to explain the main differences between theoretical and experimental data. The second one is the dependence of the circular permeability with the radius of the sample due to the internal magnetic structure. Considering a simple core–shell model for the internal magnetic structure, good agreement between theoretical and experimental data in amorphous wires is shown.