The increase of the spin-transfer torque threshold current density in coupled vortex domain walls.
The increase of the spin-transfer torque threshold current density in coupled vortex domain walls.
复制标题
耦合涡旋畴壁中自旋转移矩阈值电流密度的增加。
DOI：
10.1088/0953-8984/24/2/024210
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Lepadatu S
中科院分区：
文献类型：
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作者：
Lepadatu S
我们研究了在没有人工钉住电位的情况下，掺杂gd的弯曲Ni 80fe 20纳米线的自旋转移转矩电流密度阈值对壁运动开始的依赖。对于单涡畴壁，10%和1%的gd掺杂浓度下，阈值电流密度与线宽成反比，显著低于横向畴壁的阈值电流密度。另一方面，当Gd浓度高、线宽大时，会形成双涡畴壁，与相同线宽下的单涡畴壁相比，双涡畴壁的阈值电流密度需要增加。我们认为这是由于旋涡核心的耦合，它们具有相反的手性，因此将受到由自旋传递扭矩效应产生的相反力的作用。
We have studied the dependence on the domain wall structure of the spin-transfer torque current density threshold for the onset of wall motion in curved, Gd-doped Ni 80 Fe 20 nanowires with no artificial pinning potentials. For single vortex domain walls, for both 10% and 1% Gd-doping concentrations, the threshold current density is inversely proportional to the wire width and significantly lower compared to the threshold current density measured for transverse domain walls. On the other hand for high Gd concentrations and large wire widths, double vortex domain walls are formed which require an increase in the threshold current density compared to single vortex domain walls at the same wire width. We suggest that this is due to the coupling of the vortex cores, which are of opposite chirality, and hence will be acted on by opposing forces arising through the spin-transfer torque effect.