Stimulated infrared emission under excitation of condensed molecular dielectrics with giant pulses of a ruby laser

Stimulated infrared (IR) emission from a condensed dielectric medium under exposure to a giant pulse of a ruby laser is reported. This effect was predicted in the theoretical paper [1]. Experimental studies were carried out for a number of molecular liquids in two experimental geometries. In the first case (“in transmission” geometry) the propagation direction of the detected IR radiation coincided with that of the exciting radiation. In the second case IR radiation generated was detected in the opposite direction. The angle of divergence of IR radiation was found to be of 10⁻² rad, while the conversion efficiency with respect to the pumping intensity depended on the type of molecular liquid and varied in the range of 0.05–0.6%. Possible microscopic mechanisms of generation of IR radiation under pumping of the dielectric medium with visible or ultraviolet (UV) radiation are analyzed.