摘要
本文用铁磁共振(FMR)方法研究了 NiFe/TbCo 双层膜的交换耦合作用,其铁磁共振波谱显示出共振吸收与耦合作用间的紧密联系。交换耦合作用场增大,自旋波共振模式向一致共振峰模式退化,而一致共振线宽与交换耦合场存在着线性关系,直至自旋共振峰消失,而一致共振线宽达最大值。这些现象可用我们建立的简单的磁化强度作半抛物线型变化的模型进行解释,实验与理论基本吻合。说明由于 TbCo 膜的耦合作用,NiFe 膜的磁化强度的方向不再是一致的,共振波谱的计算必须考虑磁化矢量的空间变化。
The exchange coupling in NiFe/TbCo bilayers is studied by ferromagnetic resonance(FMR),and the spectrum shows there is a connection with the coupling.The spin resonance peaks will beabsorbed into uniform resonance peaks as the exchange coupling field becomes larger,and the perpendicu-lar uniform resonance linewidth ΔH also can be characterized linearly by the exchange coupling,till thespin resonance peaks disappear and ΔH becomes the largest.All these phenomena can be explained by oursimple model that the magnetization changes in half parobolic with the external field.With the coupling ofTbCo layer,the magnetization in NiFe layer is no longer uniform,and it varies in different position.
基金
Supported project by NSFC 58971061
关键词
共振
铁磁共振
铁磁材料
exchange coupling
spin wave
uniform resonance
resonance linewidth
