A Study of Giant Magnetoimpedance Effect and Magnetic Response in Micro-patterned F/Ag/F Magnetic Ribbon Structures (F=Co-rich Amorphous Ribbon)

摘要

The giant magnetoimpedance (GMI) effect and its field sensitivity (ξ) have been investigated in micro-patterned F/Ag/F trilayer ribbon structures in the frequency range of 1-10 MHz, F stands for Co_(69)Fe_(4.5)X_(1.5)Si_(10)B_(15) (X = Ni, Al, Cr) amorphous ribbons. It is found that the GMI ratio and ξ are enhanced in the F/Ag/F trilayer structure as compared to single-layer structure at the same condition. It has been demonstrated that the enhancement of GMI ratio and ξ results mainly from the larger effective permeability due to the closed magnetic flux path and big resistivity difference between inner and outer layer in the trilayer geometry. Importantly, the maximum GMI ratio and field sensitivity reached the largest values of 104% and 12%/Oe at a measuring frequency of 4 MHz for Al-containing sample. This result makes the F/Ag/F trilayer ribbon geometry more attractive for production of high-performance GMI-based magnetic sensors than single-layer one.