Influence of Aspect Ratio on Giant Magnetoimpedance Effect for Fe₆₇Co₁₈Si₁₁B₄ Amorphous Ribbons

Yan-Hong Ding¹，Ke Xue¹，Wei-Yan Wang¹，Xu Ma^2,3

1. School of Electrical and Electronic Engineering,Tianjin Key Laboratory of Film Electronic and Communication Devices,Tianjin University of Technology2. School of Material Science and Engineering,Tianjin University of Technology3. Tianjin Engineering Center of Near-Net-Shape Forming Technology for Metallic Materials

摘 要：The effect of sample geometry aspect ratio（l/w）on the giant magnetoimpedance（GMI）in Fe₆₇Co₁₈Si₁₁B₄amorphous ribbons was investigated systematically.The GMI profiles were measured as a function of the external magnetic field at different frequencies up to 110 MHz.The results show that there exists a critical aspect ratio（（l/w）₀=5.4）below which the maximum GMI effect and sensitivity g decrease with decreasing l/w and above which the maximum GMI effect keeps almost constant and g decreases with increasing l/w.The observed dependence on aspect ratio as（l/w）\（l/w）₀is correlated with the magnetization process:Complex domain structures emerged near the ribbon ends to decrease the magnetostatic energy,modify the transverse permeability and consequently GMI response.Contributions from transverse permeability and resistance may dominantly determine the change of GMI effect as（l/w）[（l/w）₀.

关键词：