Anisotropy Cobalt compounds Electric impedance Electron tubes Frequencies Giant magnetoresistance Magnetic permeability Magnetostriction Sensitivity analysis Substitution reactions Amorphous ribbon Asymmetric giant magnetoimpedance (AGMI) Giant magnetoimpedance Valve behavior Amorphous materials
Issue Date:
2005
Publisher:
Journal of Applied Physics
Citation:
Volume 97, Issue 10, Page 1-3
Abstract:
The influence of longitudinal field annealing on the giant magnetoimpedance (GMI) effect in
Co70 Fe5 Si15 Nb2.2 Cu0.8 B7 amorphous ribbons has been investigated. It was found that annealing in the
open air at magnetic fields smaller than the anisotropy field along the ribbon gave rise to the GMI-valve
phenomenon, while annealing at magnetic fields higher than the anisotropy field significantly reduced the
GMI effect. The GMI-valve behavior corresponding to the highest field sensitivity of GMI (125%Oe) was
observed at a frequency of 0.1 MHz in the ribbon annealed under an applied field of 2 Oe. This is ideal for
developing sensitive and quick-response magnetic sensors. The GMI-valve behavior observed in the Cobased
amorphous ribbon due to field annealing can be explained by considering the complex permeability
spectra in relation to the rotational dc magnetization. ?? 2005 American Institute of Physics.
