采用化学镀方法成功制备了自带电容构成LC共振回路的CoP/Insulator/BeCu复合结构丝.研究了这种新型复合结构丝产生LC共振型巨磁阻抗效应的特征,长度为lm=9.5cm的复合结构丝,当驱动电流频率为LC共振频率fr=29.0MHz时,LC共振型巨磁阻抗效应为487.5%,磁场灵敏度为0.46%/A.m-1,大于常规复合结构丝;远离此频率时的巨磁阻抗效应很小,巨磁阻抗效应表现出很好的频率选择特性.根据LC共振型复合结构丝的特征建立了等效电路模型,采用等效电路模型对这种复合结构丝进行了数值模拟,等效电路的数值计算与实验测量结果符合较好.从等效电路角度分析了LC共振型巨磁阻抗效应产生的机理,以及复合结构丝的长度对LC共振型巨磁阻抗效应的影响.
CoP/Insulator/BeCu composite wire incorporating a capacitor was prepared by chemical deposition. This new type of composite wire functions as an LC resonance circuit element by itself, in which large LC resonance giant magneto-impedance (LCR-GMI) effect was observed when the driving frequency approached to the LC resonance frequency. The properties of LCR- GMI in the composite wire with a length of 9.5 cm were investigated. Its LCR-GMI ratio and field sensitivity are 487.5% and 0.46 %/A · m^-1 at the resonance frequency of 29 MHz, respectively, which are higher than those of the ordinary composite wire. When the carrier frequency deviates from the resonance frequency, LCR-GMI ratio decreases obviously, showing distinct selectivity of frequency. Meanwhile, we proposed an equivalent circuit model based on the characteristics of the LC resonance composite wire, and simulated the experimental curves. The simulation results agreed well with the experimental data. Using the equivalent circuit model, we analyzed the physical mechanisms of LCR-GMI and the influence of wire length on the LCR-GMI effect.