论文标题
从理论计算中的拓扑不同磁性磁性纹理的高分辨率隧道自旋传输特性
High-resolution tunneling spin transport characteristics of topologically distinct magnetic skyrmionic textures from theoretical calculations
论文作者
论文摘要
通过使用3D-WKB组合的标量电荷和矢量旋转理论，在旋转式扫描隧道显微镜（SPENNING隧道显微镜（SPSPSM）的框架中使用3D-WKB组合的标量电荷和矢量旋转理论，通过使用3D-WKB组合的标量电荷和矢量旋转理论来报道高分辨率的隧穿电子自旋传输特性（纵向自旋电流（LSC）和自旋传输扭矩（STT）图）。对于我们的理论研究，具有各种拓扑电荷（$ Q = -3，-2，-1,0,1,2 $）的亚稳态旋转结构（pt $ _ {0.95} $ ir $ $ $ _ {0.05} $）/fe/pd（111）被认为是考虑的。使用平面外磁化的SP-STM尖端，发现作用在磁纹理的旋转上的LSC矢量的地图和所有STT矢量成分表现出与天空对象相同的拓扑。相比之下，平面内磁化尖端通常不会导致自旋传输矢量图在拓扑学上等同于基础自旋结构，除了作用在样品和尖端的旋转极性之间的特定关系的Skyrmionic纹理旋转上的LSC矢量。自旋传输载体数量的幅度表现出密切的关系，可为当前的SP-STM图像充电，而无疑是Skyrmionic拓扑。 Moreover, we find that the STT efficiency (torque/current ratio) acting on the spins of the skyrmions can reach large values up to $\sim$25 meV/$μ$A ($\sim$0.97 $h/e$) above the rim of the magnetic objects, but it considerably varies between large and small values depending on the lateral position of the SP-STM tip above the topological spin textures.引入了STT效率的简单表达方式来解释其变化。我们计算出的自旋传输矢量可用于研究拓扑式隧穿诱导的自旋式隧道诱导的自旋动力学，该动力学在拓扑上不同。
High-resolution tunneling electron spin transport properties (longitudinal spin current (LSC) and spin transfer torque (STT) maps) of topologically distinct real-space magnetic skyrmionic textures are reported by employing a 3D-WKB combined scalar charge and vector spin transport theory in the framework of spin-polarized scanning tunneling microscopy (SP-STM). For our theoretical investigation metastable skyrmionic spin structures with various topological charges ($Q=-3,-2,-1,0,1,2$) in the (Pt$_{0.95}$Ir$_{0.05}$)/Fe/Pd(111) ultrathin magnetic film are considered. Using an out-of-plane magnetized SP-STM tip it is found that the maps of the LSC vectors acting on the spins of the magnetic textures and all STT vector components exhibit the same topology as the skyrmionic objects. In contrast, an in-plane magnetized tip generally does not result in spin transport vector maps that are topologically equivalent to the underlying spin structure, except for the LSC vectors acting on the spins of the skyrmionic textures at a specific relation between the spin polarizations of the sample and the tip. The magnitudes of the spin transport vector quantities exhibit close relations to charge current SP-STM images irrespectively of the skyrmionic topologies. Moreover, we find that the STT efficiency (torque/current ratio) acting on the spins of the skyrmions can reach large values up to $\sim$25 meV/$μ$A ($\sim$0.97 $h/e$) above the rim of the magnetic objects, but it considerably varies between large and small values depending on the lateral position of the SP-STM tip above the topological spin textures. A simple expression for the STT efficiency is introduced to explain its variation. Our calculated spin transport vectors can be used for the investigation of spin-polarized tunneling-current-induced spin dynamics of topologically distinct surface magnetic skyrmionic textures.
