Dynamics of excitations of molecules driven by ultrashort laser pulses

Femtosecond laser pulses have been used to monitor chemical dynamics with the finest time- resolved details. They also offer the possibility of actually steering the molecular dynamics of a reactive system by controlling the laser pulses' parameters. Explorations of this possibility follow two main avenues: laser coherent control exploits phase coherence in weak-field excitation. Optimal control theory is being used to derive pulse shape functions which optimally favor certain objectives to be reached by the laser-induced molecular dynamics. Ideally, a complete non-perturbative characterization of the molecular response to a laser irradiation as an explicit functional of the laser pulse shape would allow for control scenarios to be inferred in a transparent manner. This complete characterization is now accessible for a number of simple molecular models with are reviewed in this communication.