Coupled electron and nuclear motion in strong laser fields

Electron motion in molecules can be initiated by a laser pulse and, through the induced charge migration, can, in turn, trigger a response from the nuclei. The generated electron-nuclear wave packets can quickly decohere, but also lead to recurrence of coherences. Presented here is a quantum dynamics study of H₂ and LiH in strong fields. No separation of electronic and nuclear motion is assumed, and no precomputed potential energy surface is required. It is shown that electron and nuclear motion are strongly coupled through the laser-pulse excitation, and already moderate nuclear excitation can substantially impact the electron dynamics. Through the full quantum dynamical treatment, coherence properties of electronic and nuclear wave function can be investigated. The nuclear motion leads to decoherences while it can also introduce recurrence of coherences.