Magnetic field driven dynamics in twisted bilayer artificial spin ice at superlattice angles
Magnetic field driven dynamics in twisted bilayer artificial spin ice at superlattice angles
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DOI：
10.1063/5.0118078
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发表时间：
2022-10-07
影响因子：
3.2
通讯作者：
Stamps, Robert L.
中科院分区：
文献类型：
--
作者：
Popy, Rehana Begum;Frank, Julia;Stamps, Robert L.
相互作用的纳米磁体的几何设计已经以称为人造自旋冰的二维阵列的形式得到了广泛的研究。这些系统通常旨在产生几何挫败感，并且对可能出现的不寻常且经常令人惊讶的现象感兴趣。先进的光刻和元件生长技术使得复杂的设计得以实现，这些设计可能涉及在三个维度上排列的元件。通过采用哑铃近似的数值模拟，我们研究了双层人造自旋冰可能的磁性行为，其中各个层相对于彼此旋转。目标是了解磁化动力学如何受到长程偶极耦合的影响，可以通过旋转改变层间距和层排列来修改磁化动力学。我们考虑双层，其中各层要么是方形的，要么是岛状风车排列的。根据磁岛的畴和畴壁结构来研究和讨论磁反转过程。对于定义双层系统的横向自旋超晶格的特殊角度，预测了不寻常的磁排序。由 AIP Publishing 独家许可出版。
Geometrical designs of interacting nanomagnets have been studied extensively in the form of two-dimensional arrays called artificial spin ice. These systems are usually designed to create geometrical frustration and are of interest for the unusual and often surprising phenomena that can emerge. Advanced lithographic and element growth techniques have enabled the realization of complex designs that can involve elements arranged in three dimensions. Using numerical simulations employing the dumbbell approximation, we examine possible magnetic behaviors for bilayer artificial spin ice, in which the individual layers are rotated with respect to one another. The goal is to understand how magnetization dynamics are affected by long-range dipolar coupling that can be modified by varying the layer separation and layer alignment through rotation. We consider bilayers where the layers are both either square or pinwheel arrangements of islands. Magnetic reversal processes are studied and discussed in terms of domain and domain wall configurations of the magnetic islands. Unusual magnetic ordering is predicted for special angles that define lateral spin superlattices for the bilayer systems. Published under an exclusive license by AIP Publishing.