title: Domain of validity of the perturbative approach to femtosecond optical spectroscopy.
abstract: We have performed numerical nonperturbative simulations of transient absorption pump-probe responses for a series of molecular model systems. The resulting signals as a function of the laser field strength and the pump-probe delay time are compared with those obtained in the perturbative response function formalism. The simulations and their theoretical analysis indicate that the perturbative description remains valid up to moderately strong laser pulses, corresponding to a rather substantial depopulation (population) of the initial (final) electronic states.
authors: Department of Chemistry, Technische Universität München, D-85747 Garching, Germany.
authors: Maxim F
authors: MF
authors: Gelin
authors: Department of Chemistry, Technische Universität München, D-85747 Garching, Germany.
authors: B Jayachander
authors: BJ
authors: Rao
authors: Department of Chemistry, Technische Universität München, D-85747 Garching, Germany.
authors: Mathias
authors: M
authors: Nest
authors: Department of Chemistry, Technische Universität München, D-85747 Garching, Germany.
authors: Wolfgang
authors: W
authors: Domcke