Tan F N, Gan W L, Ang C C I, Wong G D H, Liu H X, Poh F, Lew W S
School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore.
GLOBALFOUNDRIES Singapore Pte, Ltd., Singapore, 738406, Singapore.
Sci Rep. 2019 May 14;9(1):7369. doi: 10.1038/s41598-019-43843-x.
The use of voltage-controlled magnetic anisotropy (VCMA) via the creation of a sloped electric field has been hailed as an energy-efficient approach for domain wall (DW) propagation. However, this method suffers from a limitation of the nanowire length which the DW can propagate on. Here, we propose the use of multiplexed gate electrodes to propagate DWs on magnetic nanowires without having any length constraints. The multi-gate electrode configuration is demonstrated using micromagnetic simulations. This allows controllable voltages to be applied to neighboring gate electrodes, generating large strength of magnetic anisotropy gradients along the nanowire, and the results show that DW velocities higher than 300 m/s can be achieved. Analysis of the DW dynamics during propagation reveals that the tilt of the DW and the direction of slanted gate electrode greatly alters the steady state DW propagation. Our results show that chevron-shaped gate electrodes is an effective optimisation that leads to multi-DW propagation with high velocity. Moreover, a repeating series of high-medium-low magnetic anisotropy regions enables a deterministic VCMA-controlled high velocity DW propagation.
通过创建倾斜电场来利用电压控制磁各向异性（VCMA），被誉为一种用于畴壁（DW）传播的节能方法。然而，这种方法存在一个限制，即DW能够在其上传播的纳米线长度有限。在此，我们提出使用复用栅电极在磁性纳米线上传播DW，而不受任何长度限制。通过微磁模拟展示了多栅电极配置。这使得能够向相邻栅电极施加可控电压，沿纳米线产生高强度的磁各向异性梯度，结果表明可以实现高于300 m/s的DW速度。对DW传播过程中的动力学分析表明，DW的倾斜和倾斜栅电极的方向极大地改变了稳态DW传播。我们的结果表明，人字形栅电极是一种有效的优化方式，可实现多DW的高速传播。此外，一系列重复的高-中-低磁各向异性区域能够实现确定性的VCMA控制的高速DW传播。
