Graphene has long been known for its peculiar Dirac-like band structure
which lends it many of its remarkable properties. It is a promising material for
electronic and spintronic applications due to its high carrier mobility, low intrinsic
spin-orbit interaction and small hyperfine coupling. However, extrinsic effects
may easily dominate intrinsic mechanisms. The scattering mechanisms
investigated here are those associated with non-magnetic, charged impurities in
the substrate (e.g. SiO2) beneath a planar n-type graphene layer. Such impurities
cause an electric field that extends through the graphene and has a non-vanishing
perpendicular component. Consequently, the impurity, in addition to the
conventional spin-conserving scattering can give rise to spin-flip processes. The
latter are a consequence of a spatially varying Rashba spin-orbit interaction
caused by the electric field of the impurity in the substrate. This work focuses on
the calculation of the elastic scattering cross-sections for these mechanisms.
Additionally, relaxation times are estimated for assumed impurity concentrations.