We have studied, experimentally and theoretically, the effect of a layering sequence on the magnonic band structure in dense arrays of both asymmetric- and symmetric cross-section tri-layered Py/Cu/Fe and Fe/Cu/Py nanowires. The spin-wave dispersion for these artificial crystals has been measured with Brillouin light scattering (BLS) spectroscopy. We also carried out numerical simulations of the dispersion using an original model employing a 2D Green’s function description of the dynamic dipole field of the precessing magnetization. The presence of the Cu spacer exchange-decouples the two magnetic layers, which stabilizes two equilibrium states of static magnetization. These are the parallel and antiparallel states, for which the static magnetization vectors for the layers are either co-aligned or anti-aligned to each other, respectively. These states are stable in a range of applied fields that depend on the layer width and their ordering in the stack. The magnetization configu...

中文翻译：

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不对称和对称宽度的纳米线阵列中的集体自旋波：薄膜分层序列的影响

我们已经在实验和理论上研究了分层顺序对非对称和对称截面三层Py / Cu / Fe和Fe / Cu / Py纳米线的致密阵列中的磁致子带结构的影响。这些人造晶体的自旋波色散已通过布里渊光散射（BLS）光谱法进行了测量。我们还使用原始模型对色散进行了数值模拟，该模型采用了2D Green函数描述了进动磁化的动态偶极子场。Cu间隔物的存在使两个磁性层交换解耦，这使静态磁化的两个平衡状态稳定。这些是平行和反平行状态，对于这些状态，各层的静态磁化矢量分别彼此共对准或反对准。这些状态在取决于层宽度及其在堆栈中的顺序的一系列应用字段中是稳定的。磁化配置