三明治结构与同轴电缆结构磁性材料巨磁阻抗效应的理论研究  

Theoretical study on the giant magnetoimpedance in coaxial-cable wire and sandwiched film

作　　者：刘江涛[1] 周云松[1] 王艾玲[1] 姜宏伟[1] 郑鹉[1] 

机构地区：[1]首都师范大学物理系,北京100037

出　　处：《物理学报》2003年第11期2859-2864,共6页Acta Physica Sinica

基　　金：国家自然科学基金 (批准号 :5 0 0 710 3 8);北京市教育局基金资助的课题~~

摘　　要：根据两种具有巨磁阻抗 (GMI)效应的磁性材料实验样品 ,提出了两种理论模型 (同轴电缆结构———Cu丝外覆软磁材料的圆柱形 ;三明治结构———Cu或Ag为中间层外包软磁层的三明治膜 ) ,利用Maxwell方程和Landau_Lifshitz方程对其GMI效应的机理进行了理论研究 .证明了两种模型的差别仅仅是形状因子的不同 ,从而由理论上证实了两种结构GMI效应增强的内在一致性 .证实了在同种磁性材料情况下 ,双层结构具有结构方面的优越性 .并对照实验数据讨论了参数的影响 ,得到与实验定性相符的结果 .Two phenomenological models based on the experimental samples of giant magnetoimpedance (GMI) effect are proposed. The first model is a coaxial-cable wire composed of copper cylindrical wire electroplated with a soft magnetic, layer, and the second is a sandwiched film structured by two soft magnetic layers, within which Cu or Ag serves as the central layer. Their characteristics are discussed theoretically using Maxwell equations and Landau-Lifshitz equation. It is proved that for the two models the origination of enhancement of GMI effect is the same, and the difference between them arises from the parameter of their geometry. The structure of double deck is better than a single layer for the identical magnetic materials in GMI effect. The application of the theoretical models to real materials is examined. Predictions by using the models are qualitatively in agreement with experimental data.

关 键 词：巨磁阻抗效应 磁性材料 同轴电缆结构 三明治结构 MAXWELL方程 LANDAU-LIFSHITZ方程 软磁合金材料 

分 类 号：O441.6[理学—电磁学]