Coherent interaction of an ultrashort zero-area laser pulse with a Morse oscillator

Dissociation probabilities, energy absorption, and ground-state populations are calculated numerically for interaction of a Morse oscillator with a resonant ultrashort (tₚ{10}^{{{-}}12}$ sec) intense laser pulse as a function of intensity and pulse area in order to investigate the sensitivity of coherence phenomena to delocalization and chaos in molecule-radiation field systems. It is concluded that a zero-area pulse can reduce considerably energy absorbed by a molecule as well as dissociation probabilities for intensities below and near the chaotic region. It is found that the two-level model (describing the interaction of light resonant with the ground to first excited level transition) works well up to the intensity 10¹² W/cm², above which transitions to higher levels must be considered.