Kinetics of a transient two-beam interaction in resonant media

An experimental and theoretical investigation was made of the kinetics of a concurrent two-beam interaction in a sodium vapor. A change in the pulse shapes of the interacting beams was noted, particularly an enhancement of their modulation, as they propagated in the resonant medium. The deformation of the beams was caused by both bleaching of the medium under the action of the waves and by transient energy transfer between the waves in a dynamic grating formed in the medium.