  Spin transitions driven by a periodically varying electric potential in
dilute fluorinated graphene quantum dots are investigated. Flakes of monolayer
graphene are considered as well as electrostatic electron traps induced in
bilayer graphene. The stationary states are obtained within the tight-binding
approach and are used to the basis of eigenstates to describe the system
dynamics. The dilute fluorination of the top layer lifts the valley degeneracy
of the confined states and attenuates the orbital magnetic dipole moments due
to current circulation within the flake. Moreover, the spin-orbit coupling
introduced by the surface deformation of the top layer induced by the adatoms
allows spin flips to be driven by the AC electric field. For the bilayer
quantum dots the spin flip times is substantially shorter than the experimental
spin relaxation. Dynamical effects including many-photon and multilevel
transitions are also discussed.
