Analytic Models of Pulse Effects in Two-Photon Molecular Spectroscopy

Abstract

Recent experiments with ultrafast lasers have demonstrated that bound and dissociating motion at small internuclear distances can be resolved¹. This is accomplished using a pump-probe pulse sequence. The first pulse prepares a coherent superposition of excited state levels, the evolution of which can be followed by excitation to a final state using a probe pulse. The behaviour of the final signal, such as fluorescence from the final state, as a function of the time delay between the pulses, contains information on the nature of the intermediate potential, provided that the pulses are short enough to spacially resolve the motion.