论文标题
声驱动的磁空运动
Acoustic-Driven Magnetic Skyrmion Motion
论文作者
论文摘要
磁性天空具有开发新型自旋装置的巨大潜力。天空的电操作主要依赖于电流诱导的自旋轨道扭矩。一个最近的理论模型表明，表面声波（SAW）可以更有效地操纵天空，这是一种弹性波，可以通过磁弹性效应将磁矩与磁矩搭配。但是，仍然缺少由SAW驱动的Skyrmions的定向运动。在这里，我们通过实验证明了Néel-type Skyrmions在TA/COFEB/MGO/TA多层中的运动，这些多层由芯片压电传感器的繁殖SAW脉冲驱动。我们的结果表明，具有纵向和剪切垂直位移（Rayleigh Wave）的弹性波捕获了Skyrmions，而剪切水平波有效地驱动了Skyrmions的运动。特别是，观察到沿锯繁殖方向的纵向运动和由于拓扑电荷引起的横向运动，并通过我们的微磁模拟进一步证实。这项工作证明了一种基于声波来操纵天空的有前途的方法，这可以为超低功率旋转的新机会提供新的机会。
Magnetic skyrmions have great potential for developing novel spintronic devices. The electrical manipulation of skyrmions has mainly relied on current-induced spin-orbit torques. A recent theoretical model suggested that the skyrmions could be more efficiently manipulated by surface acoustic waves (SAW), an elastic wave that can couple with magnetic moment through magnetoelastic effect. However, the directional motion of skyrmions that is driven by SAW is still missing. Here, we experimentally demonstrate the motion of Néel-type skyrmions in Ta/CoFeB/MgO/Ta multilayers driven by propagating SAW pulses from on-chip piezoelectric transducers. Our results reveal that the elastic wave with longitudinal and shear vertical displacements (Rayleigh wave) traps skyrmions, while the shear horizontal wave effectively drives the motion of skyrmions. In particular, a longitudinal motion along the SAW propagation direction and a transverse motion due to topological charge, are observed and further confirmed by our micromagnetic simulations. This work demonstrates a promising approach based on acoustic waves for manipulating skyrmions, which could offer new opportunities for ultra-low power spintronics.
