Modeling of asymmetric giant magnetoimpedance in amorphous ribbons with a surface crystalline layer

摘要

A model describing the asymmetric giant magnetoimpedance (GMI) infield-annealed amorphous ribbons is proposed. It is assumed that the ribbonconsists of an inner amorphous core and surface hard magnetic crystallinelayers. The model is based on a simultaneous solution of linearizied Maxwellequations and Landau-Lifshitz equation. The coupling between the surface layersand the amorphous core is described in terms of an effective bias field.Analytical expressions for the frequency and field dependences of the ribbonimpedance are found. The calculated dependences are in a qualitative agreementwith results of experimental studies of the high-frequency asymmetric giant GMIin field-annealed amorphous ribbons.