标题： 受电流驱动的合成反铁磁双层中的受挫磁涡旋动力学 显示英文标题

标题： Current-Driven Dynamics of Frustrated Skyrmions in a Synthetic Antiferromagnetic Bilayer

摘要： 我们报告了在反铁磁交换耦合双层系统中受电流驱动的受挫自旋涡旋的动力学，其中双层自旋涡旋由两个具有相反自旋涡旋数的单层自旋涡旋组成$Q$。我们表明，在平面内电流驱动下，双层自旋涡旋沿直线移动，而在垂直方向上电流驱动下，双层自旋涡旋沿圆形路径移动。我们发现，在$\beta/\alpha$的大比例下，双层自旋涡旋的平面内电流驱动迁移率远优于单层自旋涡旋，其中$\alpha$和$\beta$分别表示阻尼参数和非绝热自旋转移扭矩强度。此外，当$\alpha$较小时，双层自旋涡旋的垂直方向电流驱动迁移率远优于单层自旋涡旋。我们还揭示，一个双层自旋涡旋（由具有$Q=\pm 2$的单层自旋涡旋组成）可以在垂直方向电流驱动下分离为两个双层自旋涡旋（由具有$Q=\pm 1$的单层自旋涡旋组成）。我们的结果可能有助于设计基于受挫多层磁体的自旋电子器件。 显示英文摘要

摘要： We report the current-driven dynamics of frustrated skyrmions in an antiferromagnetically exchange coupled bilayer system, where the bilayer skyrmion consists of two monolayer skyrmions with opposite skyrmion numbers $Q$. We show that the in-plane current-driven bilayer skyrmion moves in a straight path, while the out-of-plane current-driven bilayer skyrmion moves in a circular path. It is found that the in-plane current-driven mobility of a bilayer skyrmion is much better than the monolayer one at a large ratio of $\beta/\alpha$, where $\alpha$ and $\beta$ denote the damping parameter and non-adiabatic spin transfer torque strength, respectively. Besides, the out-of-plane current-driven mobility of a bilayer skyrmion is much better than the monolayer one when $\alpha$ is small. We also reveal that one bilayer skyrmion (consisting of monolayer skyrmions with $Q=\pm 2$) can be separated to two bilayer skyrmions (consisting of monolayer skyrmions with $Q=\pm 1$) driven by an out-of-plane current. Our results may be useful for designing skyrmionic devices based on frustrated multilayer magnets.