Spin-orbit-torque-induced magnetic domain wall motion in Ta/CoFe nanowires with sloped perpendicular magnetic anisotropy.
Spin-orbit-torque-induced magnetic domain wall motion in Ta/CoFe nanowires with sloped perpendicular magnetic anisotropy.
复制标题
具有倾斜垂直磁各向异性的 Ta/CoFe 纳米线中自旋轨道扭矩引起的磁畴壁运动
DOI：
10.1038/s41598-017-02208-y
复制
发表时间：
2017-05-17
影响因子：
4.6
通讯作者：
Yang C
中科院分区：
文献类型：
--
作者：
Zhang Y;Luo S;Yang X;Yang C
在磁各向异性梯度材料中，自旋-轨道-力矩诱导磁化行为因其有趣的科学原理和潜在的应用前景而受到人们的关注。大多数的磁化行为微观起源于磁畴壁运动，这可以精确地描述使用标准的合作坐标方法（CCM）。然而，利用CCM对具有磁各向异性梯度的材料中畴壁运动的研究还很缺乏。采用CCM方法，建立了一组定量描述具有弱Dzyaloshinskiii-Moriya相互作用和磁各向异性梯度的Ta/CoFe纳米轨道中畴壁自旋-轨道-力矩诱导运动的方程.数值求解方程组，解决方案是类似的微磁模拟。结果表明，畴壁沿着向各向异性的增强起到了阻碍畴壁运动的作用。与此相反，畴壁可以被推动以在各向异性减小的方向上移动，与恒定各向异性的情况相比，速度被加速超过两倍。通过各向异性工程的这种实质性速度操纵在设计具有高阅读速度的新型磁信息器件中是重要的。
In materials with the gradient of magnetic anisotropy, spin-orbit-torque-induced magnetization behaviour has attracted attention because of its intriguing scientific principle and potential application. Most of the magnetization behaviours microscopically originate from magnetic domain wall motion, which can be precisely depicted using the standard cooperative coordinate method (CCM). However, the domain wall motion in materials with the gradient of magnetic anisotropy using the CCM remains lack of investigation. In this paper, by adopting CCM, we established a set of equations to quantitatively depict the spin-orbit-torque-induced motion of domain walls in a Ta/CoFe nanotrack with weak Dzyaloshinskii–Moriya interaction and magnetic anisotropy gradient. The equations were solved numerically, and the solutions are similar to those of a micromagnetic simulation. The results indicate that the enhanced anisotropy along the track acts as a barrier to inhibit the motion of the domain wall. In contrast, the domain wall can be pushed to move in a direction with reduced anisotropy, with the velocity being accelerated by more than twice compared with that for the constant anisotropy case. This substantial velocity manipulation by anisotropy engineering is important in designing novel magnetic information devices with high reading speeds.