The influence of moving domain walls on the appearance of the second harmonic in the magnetoimpedance spectrum of a cobalt-based amorphous microwire

Abstract

We have studied the influence of moving domain walls (DWs) on the magnetoimpedance of a cobalt-based amorphous microwire. A model describing the DW motion in the electric field of an alternating current in the absence of a skin effect is proposed. When the current amplitude exceeds a certain threshold value, the DW motion leads to the appearance of a second harmonic component in the frequency spectrum of the sample response voltage. The second harmonic amplitude has been studied as a function of the external longitudinal magnetic field, the current frequency, and the angle of deviation of the microwire anisotropy axis from the circular direction. The sensitivity of the second harmonic to the external magnetic field can be significantly higher than that of the first harmonic.