Electric Conductivity of a Metallic Ferromagnet and Magnetization Process

Abstract The dependence of the conductivity and the magnetoresistance of a multi‐domain metallic ferromagnet on the magnetization when current flows along a domain wall is studied. The expression for the conductivity is obtained as function of x‐coordinate which is normal to the domain wall plane. It is shown that the region of current localization in a compensated ferromagnet has a size in the x‐coordinate of the order of the cyclotron radius near a single domain wall and becomes of the order of the decreasing domain width under magnetization. The magnetoresistance sharply increases in an external magnetic field near the saturation region. A comparison is made with the experimental data on the magnetoresistance of a ferromagnet with domain structure. It is shown that the appearance of nuclei of reverse‐magnetized domains leads to a resistance drop in the beginning of the magnetization process.