Guan Yicheng, Zhou Xilin, Li Fan, Ma Tianping, Yang See-Hun, Parkin Stuart S P
Max Planck Institute for Microstructure Physics, 06120, Halle, Germany.
Nat Commun. 2021 Aug 18;12(1):5002. doi: 10.1038/s41467-021-25292-1.
The current induced motion of domain walls forms the basis of several advanced spintronic technologies. The most efficient domain wall motion is found in synthetic antiferromagnetic (SAF) structures that are composed of an upper and a lower ferromagnetic layer coupled antiferromagnetically via a thin ruthenium layer. The antiferromagnetic coupling gives rise to a giant exchange torque with which current moves domain walls at maximum velocities when the magnetic moments of the two layers are matched. Here we show that the velocity of domain walls in SAF nanowires can be reversibly tuned by several hundred m/s in a non-volatile manner by ionic liquid gating. Ionic liquid gating results in reversible changes in oxidation of the upper magnetic layer in the SAF over a wide gate-voltage window. This changes the delicate balance in the magnetic properties of the SAF and, thereby, results in large changes in the exchange coupling torque and the current-induced domain wall velocity. Furthermore, we demonstrate an example of an ionitronic-based spintronic switch as a component of a potential logic technology towards energy-efficient, all electrical, memory-in-logic.
当前由电流诱导的磁畴壁运动构成了几种先进自旋电子技术的基础。在由通过薄钌层反铁磁耦合的上、下铁磁层组成的合成反铁磁（SAF）结构中，发现了最有效的磁畴壁运动。当两层的磁矩匹配时，反铁磁耦合会产生一个巨大的交换转矩，电流利用这个转矩以最大速度移动磁畴壁。在此我们表明，通过离子液体门控，可以以非易失性方式将SAF纳米线中磁畴壁的速度可逆地调节数百米/秒。离子液体门控在很宽的栅极电压窗口内导致SAF中上部磁性层的氧化发生可逆变化。这改变了SAF磁性特性中的微妙平衡，从而导致交换耦合转矩和电流诱导的磁畴壁速度发生大幅变化。此外，我们展示了一个基于离子电子学的自旋电子开关示例，作为一种潜在逻辑技术的组件，用于实现节能、全电气、逻辑中存储的功能。
