A seamless graphene spin valve based on proximity to van der Waals magnet Cr₂Ge₂Te₆

Abstract

Pristine graphene is potentially an ideal medium for transporting spin information. Proximity effects—where a neighbouring material is used to alter the properties of a material in adjacent (or proximitized) regions—can also be used in graphene to generate and detect spins by acquiring spin–orbit coupling or magnetic exchange coupling. However, the development of seamless spintronic devices that are based only on proximity effects remains challenging. Here we report a two-dimensional graphene spin valve that is enabled by proximity to the van der Waals magnet Cr2Ge2Te6. Spin precession measurements show that the graphene acquires both spin–orbit coupling and magnetic exchange coupling when interfaced with the Cr2Ge2Te6. This leads to spin generation by both electrical spin injection and the spin Hall effect, while retaining spin transport. The simultaneous presence of spin–orbit coupling and magnetic exchange coupling also leads to a sizeable anomalous Hall effect.