Gate tunability of highly efficient spin-to-charge conversion by spin Hall effect in graphene proximitized with WSe2

Abstract

The proximity effect opens ways to transfer properties from one material into another and is especially important in two-dimensional (2D) materials. In van der Waals heterostructures, transition metal dichalcogenides (TMDs) can be used to enhance the spin–orbit coupling of graphene leading to the prediction of gate controllable spin-to-charge conversion (SCC). Here, we report for the first time and quantify the spin Hall effect (SHE) in graphene proximitized with WSe2 up to room temperature. Unlike in other graphene/TMD devices, the sole SCC mechanism is the SHE and no Rashba–Edelstein effect is observed. Importantly, we are able to control the SCC by applying a gate voltage. The SCC shows a high efficiency, measured with an unprecedented SCC length larger than 20 nm. These results show the capability of 2D materials to advance toward the implementation of novel spin-based devices and future applications.