Manipulating electronic couplings and nonadiabatic nuclear dynamics with strong laser pulses

We demonstrate the possibility of manipulating the coupling between two (optically bright and optically dark) excited electronic states and of controlling the ensuing nuclear wave packet dynamics via a strong laser pulse, which couples the ground and the bright electronic state. The control of the wave packet dynamics is implemented through the creation of a highly nonequilibrium distribution in the bright-dark vibronic manifold. The distribution is produced due to the combined effect of the external pulse (through Rabi cycling) and the system itself (through the electronic interstate coupling). The induced wave packet dynamics persists long after the pulse is over, both in the isolated and in the dissipative system. The effects are robust and are achieved by varying the strength and duration of a Gaussian pulse, that is, no careful tuning of the pulse shape is required. Possible applications of our results include the strong-pulse control of electron transfer as well as the enhancement and detection of intramolecular electronic coupling via strong-pulse spectroscopy.