论文标题
WSE2中Valley Hall效应产生的自旋扭矩
Spin Torque Generated by Valley Hall Effect in WSe2
论文作者
论文摘要
单层过渡金属二进制基因源是旋转三位型的有前途的材料，因为它们具有稳健的自旋valley锁定价状态，从而通过山谷霍尔效应有效地进行了旋转的电荷转换，并具有具有长的自旋扩散长度的数百纳米纳米的非平衡旋转。在这项工作中，我们表明，在WSE2单层中，由Valley Hall效应引起的纯山谷电流在隧道结构中赋予了覆盖的Fe或Cofe的磁化。发现扭矩效率与常规垂直磁性隧道连接处的扭矩效率相当，并且可以通过WSE2中的Valley Hall角进一步优化。自旋扭矩的山谷性质在平面构型中产生了平面外阻尼状的扭矩，消失的电荷传输垂直于平面到平面以及通过门控的扭矩效率可调节。
Monolayer transition metal dichalcogenides are promising materials for spintronics due to their robust spin-valley locked valence states, enabling efficient charge-to-spin conversion via valley Hall effect with non-equilibrium spins possessing long spin diffusion lengths of hundreds of nanometers. In this work, we show that the injection of a pure valley current, induced by valley Hall effect in a WSe2 monolayer, imparts a spin torque on the magnetization of an overlaid Fe or CoFe in a tunneling structure. The torque efficiency is found to be comparable to that in conventional perpendicular magnetic tunnel junctions and can be further optimized with valley Hall angle in WSe2. The valley nature of the spin torque gives rise to out-of-plane damping-like torques in a current-in-plane configuration, vanishing charge transport perpendicular-to-the-plane as well as torque efficiency tunable through gating.
