Some characteristics of formation of volume dynamic holograms by concurrent waves propagating in resonant atomic media

An investigation was made of the transient process of formation of volume dynamic holograms by light within the spectral limits of the D₂ resonant absorption line of sodium. The observed asymmetry of the spectral distribution of the gain of the signal waves in the case of a concurrent interaction between four beams was attributed to different mechanisms of the interaction, the main of which were a four-wave interaction in the long-wavelength wing and transient two-beam energy transfer in the short-wavelength wing. The results obtained were used to recommend an experimental method for the determination of the relative contributions of these processes to the amplification of signal waves.