Graphene exhibits excellent properties for spin transport including the long spin diffusion lengths at room temperature (up to 30 microns). This results from a small intrinsic spin-orbit coupling, leading to relatively slow spin relaxation rates, in combination with relatively high mobilities. The low spin-orbit coupling, however, also has some downsides, mainly that the electrical control of spin is difficult to achieve. In this talk, I will discuss one of the emerging approaches to address this limitation, namely the use of spin proximity effect in heterostructures. One type of effect is the proximity exchange coupling, where spins in graphene are exchange coupled to the magnetization of an adjacent ferromagnetic insulator. This can produce effective magnetic fields to induce precessional dynamics and magnetically-controlled spin relaxation . Another type of effect is the proximity spin-orbit coupling, where spins in graphene experience substantially increased spin-orbit coupling due to interactions with an adjacent heavy metal layer or transition metal dichalcognide (TMDC) 2D semiconductor. The role of electrostatic gating as a proposed method for tuning the spin proximity effect will be discussed, as well as the surprising observation of intrinsic gate-tunable spin lifetime anisotropy in Bernal stacked bilayer graphene . This latter result is one of the first instances of an intrinsic band structure spin-orbit effect observed in graphene spin valves.
Relevant references from presenter:
 Singh et al., Phys. Rev. Lett. 118, 187201 (2017).
 Xu et al., Phys. Rev. Lett. 121, 127703 (2018).