Asymmetric giant magnetoimpedance in annealed amorphous [formula omitted] wire under the circumferential field

The permeability spectra and asymmetric giant magnetoimpedance (GMI) have been measured in annealed amorphous Co-based wire under the circumferential field produced by the bias current. The permeability from the wall motion of core domains is nearly constant; however, the permeability from rotational magnetization of shell domains increases with bias current. The asymmetric GMI profile is revealed for the bias current over 4.5 mA, due to the influence of unidirectional bias field on the wall motion in the circumferential direction, and maximum field sensitivity is observed for the bias current of 4.5 mA.