论文标题
在面内磁化系统中通过自旋轨道扭矩传播的域壁传播
Domain wall propagation by spin-orbit torques in in-plane magnetized systems
论文作者
论文摘要
通过分析和微磁模拟研究了阻尼状的自旋轨道扭矩（DL SOT）对平面磁化软轨道中磁性域壁（DWS）的影响。我们发现DL SOT驱动涡流DWS，而横向DWS（软轨道中的另一个典型DW结构）仅在存在Dzyaloshinskii-Moriya相互作用（DMI）时传播。 SOT驱动器可以增加，并且比自旋转移扭矩（STT）更有效，因此可能会大大受益于需要面内DW的应用。我们基于硫核方程的分析表明，驱动力是由几何限制或DMI引起的DW结构的循环失真引起的。这种失真较高，SOT在较窄，更薄的轨道上更有效。这些结果表明，仅通过简单地考虑结构中心的有效领域，这是一个不可能的但经常使用的估计来理解SOT的效果。我们还表明，可以通过比较同一轨道中不同涡流DW结构的运动来确定STT和DL SOT的相对大小。
The effect of damping-like spin-orbit torque (DL SOT) on magnetic domain walls (DWs) in in-plane magnetised soft tracks is studied analytically and with micromagnetic simulations. We find that DL SOT drives vortex DWs, whereas transverse DWs, the other typical DW structure in soft tracks, propagate only if the Dzyaloshinskii-Moriya interaction (DMI) is present. The SOT drive can add to, and be more efficient than, spin-transfer torque (STT), and so may greatly benefit applications that require in-plane DWs. Our analysis based on the Thiele equation shows that the driving force arises from a cycloidal distortion of the DW structure caused by geometrical confinement or DMI. This distortion is higher, and the SOT more efficient, in narrower, thinner tracks. These results show that the effects of SOT cannot be understood by simply considering the effective field at the center of the structure, an ill-founded but often-used estimation. We also show that the relative magnitude of STT and DL SOT can be determined by comparing the motion of different vortex DW structures in the same track.
