Near-room temperature electrical control of spin and valley Hall effect in monolayer WSe2 transistors for spintronic applications

Monolayer transition metal dichalcogenide (TMD) materials have exciting potential for applications in spintronics. Due to the monolayer geometry and strong spin-orbit coupling, they are predicted to have a coupled spin and valley Hall effect (SVHE), where valley-polarized conduction carriers have opposite spin [1, 2, 3]. This could provide a valley-preserved spin Hall effect for switching future magnetic memories. WSe
₂
is an attractive 2D material in this context because of its large valence band spin splitting. Lifetimes of spin and valley polarized carriers in monolayer WSe
₂
have been measured from 0.7 ns to 1 μs at 10 K [4, 5, 6]. Such long lifetimes combined with reasonable mobilities lead to spin-valley accumulation that can be imaged via the magneto-optical Kerr effect (MOKE). For use in applications, it is necessary to electrically control the SVHE and push it towards room temperature.