Spin Transport in High-Quality Suspended Graphene Devices

We measure spin transport in high mobility suspended graphene (mu approximate to 10(5)cm(2)/(V s)), obtaining a (spin) diffusion coefficient of 0.1 m(2)/s and giving a lower bound on the spin relaxation time (tau(s) approximate to 150 ps) and spin relaxation length (lambda(s) = 4.7 mu m) for intrinsic graphene. We develop a theoretical model considering the different graphene regions of our devices that explains our experimental data.