Two-photon processes and the dynamic Stark effect in molecular lasers with pulsed optical pumping

A theoretical analysis is made of the operation of a pulsed laser with resonant optical pumping (as applied to NH₃) operating at moderate pressures of the active medium. It is found that stimulated two-photon transitions and the dynamic Stark effect play an important part in these systems. These factors are responsible for the possibility of varying the radiation frequency during formation of a lasing pulse, for the existence of an optimal pump power for which the lasing intensity has a maximum, and also for the existence of an optimal detuning of the pump radiation frequency from the center of the vibrational-rotational transition at a given excitation intensity.