Yu Ziyang, Zhang Yue, Zhang Zhenhua, Cheng Ming, Lu Zhihong, Yang Xiaofei, Shi Jing, Xiong Rui
Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, People's Republic of China.
Nanotechnology. 2018 Apr 27;29(17):175404. doi: 10.1088/1361-6528/aaaf35. Epub 2018 Feb 14.
In this article, we present our numerical investigation about the spin-orbit-torque induced domain-wall (DW) motion in a synthetic antiferromagnetic multilayer nanotrack. This nanotrack was composed by two ferromagnetic (FM) layers with a RKKY inter-layer antiferromagnetic (AFM) exchange coupling. The velocity of DW was well manipulated by varying parameters including inter-layer exchange constant, the Dzyaloshinskii-Moriya interaction (DMI) strength, the current density and the magnetic anisotropy. The DW velocity was found to be strictly related to the orientation of the moments in the two FM layers. When the interlayer exchange constant or the DMI constant were larger than a critical value, there was a large angle between the moments in one FM layer and that in the other one under the current, and the DW was driven to move at an ultrahigh speed (around 10 000 m s). However, when the DMI or the AFM exchange coupling was weaker than the critical value, the moments in one FM layer were parallel to that in the other one under the current, and the velocity was significantly reduced.
在本文中，我们展示了关于自旋轨道扭矩诱导合成反铁磁多层纳米轨道中畴壁（DW）运动的数值研究。该纳米轨道由两个具有RKKY层间反铁磁（AFM）交换耦合的铁磁（FM）层组成。通过改变包括层间交换常数、Dzyaloshinskii-Moriya相互作用（DMI）强度、电流密度和磁各向异性等参数，DW的速度得到了很好的控制。发现DW速度与两个FM层中磁矩的取向严格相关。当层间交换常数或DMI常数大于临界值时，在电流作用下，一个FM层中的磁矩与另一个FM层中的磁矩之间存在很大角度，DW被驱动以超高速（约10000 m/s）移动。然而，当DMI或AFM交换耦合弱于临界值时，在电流作用下，一个FM层中的磁矩与另一个FM层中的磁矩平行，速度显著降低。
