Theoretical Study of Electron Dynamics in Graphene Interacting with Ultrafast and Ultrastrong Laser Pulses

In this paper, we investigate the dynamics of electron system in graphene monolayer from theoretical and numerical points of view. We have shown that graphene subjected to an ultrafast (near-single-oscillation pulse) and strong (on the order of interatomic field) pulse, exhibits fundamental behavior dramatically different from both insulators and metals. In such an ultrafast and ultrastrong field, the electron dynamics is coherent and is described by the time-dependent Schrodinger equation. Electron transfer from the Valence band to the Conduction band is deeply irreversible which implies non-adiabaticity of the system in which the residual Conduction band population (after the pulse ends) is close to the maximum one. The residual Conduction band populations as a function of wave vector is non-uniform with a few strongly localized spots near the Dirac points, at which the Conduction band is almost fully populated.