Application of optimal control theory to ultrafast nonresonant multiphoton transitions in polyatomic molecules

Optimal control theory (OCT) including nonresonant multiphoton transitions (NMT) in the femtosecond time regime has been implemented. The NMT process is modelled using an effective time-dependent Schrödinger equation, which considers a reduced space of the two levels which are involved in the transition, coupled to a density of high-lying off-resonant states. The specification of OCT to two-photon transitions is done within the rotating wave approximation. As an application, the transfer and displacement of a wavepacket in the organometallic system CpMn(CO)3, from the ground to an electronically excited state using two nonresonant photons, is simulated.