论文标题
混合超导体/铁磁体结构中拓扑磁纹理引起的Meissner电流
Meissner Currents Induced by Topological Magnetic Textures in Hybrid Superconductor/Ferromagnet Structures
论文作者
论文摘要
由于前者在Spintronics中的潜在应用以及作为实现非客气拓扑超导体的另一个平台，最近与超导体接近的拓扑旋转构型最近引起了极大的兴趣。它们在这些领域的应用需要精确了解现有的交换领域和/或流浪场，因此对于研究这些系统至关重要。在这里，我们确定在F的超导/铁磁/超导体/超导体（s/f/s）连接中，在F中产生的各种非孔磁纹理产生的有效散落场和Meissner电流。不均匀性是由于具有平坦结构壁（DW）或由隔离的奇拉（Skiral Magnetic Magnetic Magnetic Magnetic Skyrmion（Sk）引起的不均匀性而引起的。我们同时考虑Bloch-和Néel-type SK，并详细分析不同类型的DW的周期结构（即Bloch-type DW（BDW）和Néel-type dw（NDW），具有有限宽度的dw（ndw），具有内在和超过平面磁化磁化强度磁化强度。对于Bloch和Néel-type磁纹理而言，磁场和Meissner电流的空间依赖性在质量上有所不同。尽管上下S中的空间分布对于Bloch型SK和DW是相同的，但对于Néel-type磁纹理而言，它们是不对称的。确定临界温度并与流浪场的矢量电势相关的depairing因子可以在磁性域的中心具有最大值，但正如我们所显示的，在DW上方。对于SK的最大值，位于SK半径内的有限距离。基于此，我们研究了DW存在的超导性的成核。由于Néel型结构的不对称性，上下S中的临界温度有所不同。获得的结果也可以应用于S/F双层。
Topological spin configurations in proximity to a superconductor have recently attracted great interest due to the potential application of the former in spintronics and also as another platform for realizing non-trivial topological superconductors. Their application in these areas requires precise knowledge of the existing exchange fields and/or the stray-fields which are therefore essential for the study of these systems. Here, we determine the effective stray-field and the Meissner currents in a Superconductor/Ferromagnet/Superconductor (S/F/S) junction produced by various nonhomogenous magnetic textures in the F. The inhomogeneity arises either due to a periodic structure with flat domain walls (DW) or is caused by an isolated chiral magnetic skyrmion (Sk). We consider both Bloch- and Néel-type Sk and also analyze in detail the periodic structures of different types of DW's-- that is Bloch-type DW (BDW) and Néel-type DW (NDW) of finite width with in- and out-of-plane magnetization vector. The spatial dependence of the fields and Meissner currents are shown to be qualitatively different for the case of Bloch- and Néel-type magnetic textures. While the spatial distributions in the upper and lower S are identical for Bloch-type Sk and DW's they are asymmetric for the case of Néel-type magnetic textures. The depairing factor, which determines the critical temperature and which is related to vector potential of the stray-field, can have its maximum at the center of a magnetic domain but also, as we show, above the DW. For Sk's the maximum is located at a finite distance within the Sk radius. Based on this, we study the nucleation of superconductivity in the presence of DW's. Because of the asymmetry for Néel-type structures, the critical temperature in the upper and lower S is expected to be different. The obtained results can also be applied to S/F bilayers.
