Effects of the Edge Shape of the Elements on the Properties of Stepped Giant Magnetoimpedance

The effects of the element-edge shape on the stepped impedance properties are investigated in this paper. Stepped giant magnetoimpedance elements with three types of edge shape were fabricated, and their impedance profiles were examined. The stepped impedance property of all elements was obtained, and it was confirmed by domain observation that impedance jumps occurred at the transition points of the domain structure between the single and multiple domains. The strength of the magnetic field in which the impedance jump occurs depends on the edge shape. The impedance jump that occurs under the smallest field strength for elements with edge shape broadens gradually toward the end of the element, whereas that under the strongest field strength for elements with edge shape becomes sharp. The difference in the properties of the stepped impedance due to the different edge shapes is explained by the change in the shape anisotropy effect based on a simplified domain-structure model.