Resonant inelastic transmission through a time-modulated region in graphene

We investigate a number of resonant transmission processes through a time-modulated-potential region in graphene. Incident energies covering both low and high energy regimes are included, and the time-dependent transmission is treated within a tight-binding model. Three main results are obtained. Dip structures in the transmission are obtained when a band edge is involved. It can occur in the low energy regime, if the graphene is gapped, or in the high energy regime, when a graphene band edge is in the energy neighborhood. These dip structures cause significant deviation from Klein-type perfect transmission. Non-typical Fabry-P\'{e}rot interference is observed when, staying upon a dip structure condition, the transmission exhibits an oscillation that has a longer than expected period in $L$, the width of the time-modulated region. Central band refocusing is found in the low energy regime, where the dominance in the transmission by the central-band will occur periodically with $L$. In all these results, we have demonstrated and analyzed detail intricate resonant interplays between sideband processes.