Quantum optoelectronic devices capable of isolating a target degree of freedom (DoF) from other DoFs have allowed for new applications in modern information technology. Many works on solid-state spintronics have focused on methods to disentangle the spin DoF from the charge DoF¹, yet many related issues remain unresolved. Although the recent advent of atomically thin transition metal dichalcogenides (TMDs) has enabled the use of valley pseudospin as an alternative DoF^2,3, it is nontrivial to separate the spin DoF from the valley DoF since the time-reversal valley DoF is intrinsically locked with the spin DoF⁴. Here, we demonstrate lateral TMD–graphene–topological insulator hetero-devices with the possibility of such a DoF-selective measurement. We generate the valley-locked spin DoF via a circular photogalvanic effect in an electric-double-layer WSe₂ transistor. The valley-locked spin photocarriers then diffuse in a submicrometre-long graphene layer, and the spin DoF is measured separately in the topological insulator via non-local electrical detection using the characteristic spin–momentum locking. Operating at room temperature, our integrated devices exhibit a non-local spin polarization degree of higher than 0.5, providing the potential for coupled opto-spin–valleytronic applications that independently exploit the valley and spin DoFs.

能够将目标自由度（DoF）与其他DoF隔离的量子光电设备已经在现代信息技术中得到了新的应用。固态自旋电子学上的许多工作都集中在使自旋DoF与电荷DoF ¹分离的方法上，但是许多相关问题仍未解决。尽管最近出现的原子薄的过渡金属二硫属金属双金属卤化物（TMDs）使得谷值伪自旋可以用作替代DoF ^2,3，但自旋DoF与谷值DoF分离并不容易，因为时间反转谷点DoF本质上是锁定的与旋转自由度⁴。在这里，我们演示了横向TMD-石墨烯-拓扑绝缘体异质器件，并可能进行此类DoF选择性测量。我们在双电层WSe ₂晶体管中通过圆形光电效应产生了谷值锁定自旋DoF 。然后，谷锁定的自旋光载体在亚微米长的石墨烯层中扩散，并且使用特征性的自旋动量锁定，通过非局部电学检测在拓扑绝缘体中分别测量自旋DoF。我们的集成器件在室温下运行，其非局部自旋极化度高于0.5，为耦合光-自旋-谷电子应用提供了潜力，可独立地利用波谷和自旋DoF。