Study of proximity induced SOC and spin injection in graphene - multilayer WSe₂ Van der Waals structures

Graphene with long electron spin diffusion length (up to 30 µm) has emerged as a promising two dimensional (2D) material for studying spin electronics.¹ However, it lacks spin orbit coupling (SOC) in its pristine form which could facilitate electrical manipulation of both charge and spin transport. However, 2D transition metal di-chalcogenides (TMD) like WSe₂ have strong SOC which can be placed on top of graphene to investigate proximity-induced SOC in graphene.² We study such interaction via probing spin transport in graphene encapsulated by multilayer WSe₂ (5-10 nm thick) as a function of electrical tuning of charge carrier concentration in graphene and WSe₂. Further, spin injection into graphene using WSe₂ is demonstrated to understand the nature of interface in order to realize all 2D spin electronics devices.

[1] Marc Drögeler., NanoLett. 16, 3533−3539 (2016).
[2] S. Omar., PRB 95, 081404(R) (2017).
[3] B. N. Madhushankar., Manuscript in preparation.