Laser-induced charge transfer and photodesorption of Cs at Cu(111): quantum dynamical model simulations

Abstract

We present electronic and nuclear quantum model simulations for the direct, laser-induced charge transfer from a Cu(111) surface state to an unoccupied resonance state of an adsorbed Cs atom, and the resulting nuclear dynamics. Based on a modified one-electron model potential adopted from Chulkov et al., we determine energies and lifetimes of electronic states of Cs/Cu(111) at low coverage. In addition, semiempirical nuclear potential energy surfaces of the electronic ground and the antibonding excited states along the Cs-Cu distance are designed and used for nuclear dynamics. For both models, electronic and nuclear, we perform open-system quantum dynamics with the goals (i) to estimate the excitation (charge transfer) and Cs desorption probabilities and (ii) to optimize the charge-transfer process by pulse shaping and the desorption of Cs from the Cu surface by vibrationally exciting the Cs-Cu bond.