A theoretical model for the giant magnetoimpedance in ribbons of amorphous soft-ferromagnetic alloys

Giant magnetoimpedance (GMI) measured in ribbons of the soft ferromagnet Co75-xFexSi15B10 annealed in the presence of a transverse magnetic field exhibits peaks in its field dependence. The GMI is strongly dependent on the magnitude of the longitudinal field and on the frequency of the applied current. We present a theoretical model which explains the existence of the peaks and its frequency dependence. The model is based on the skin depth effect and on the domain-wall motion due to the magnetic field and the ac current. (C) 1996 American Institute of Physics.