Quasiprobability distribution dynamics of an initially one-mode coherent photon field interacting with two- and three-state molecular systems

The dynamics of quasiprobability (Q function) distributions of an initially one-mode coherent field interacting with two- and three-state molecular systems are investigated by using a numerically exact approach. In a near-resonant external photon field, the collapses and revivals of the Rabi oscillations of molecular populations are found to be concerned with the asymmetric splitting of the Q function distribution peak, the counterrotating of the asymmetric split peaks and the colliding of the split peaks. It is also found that there are remarkable differences in the features of the Q function distribution dynamics between the two- and three-state molecular systems.