The influence of an electric current density on the complex permeability

Abstract
In an attempt to influence the domain wall damping, an ac electric current was driven through contacted ferrite ring cores and parallelepipeds in different directions. The dependence of magnetic properties on current density, phase shift between the winding current and material current and current direction was measured. Changes in magnetic flux due to the additional magnetic field arising from the material current were considered. Variations of the complex permeability as a function of current phase shift and coaxial or radial direction were observed. Changes in damping and resonance frequency can be interpreted as due to the interaction of the electric current with domain walls. The observed effects can be explained by the domain drag effect.