Intensity and Gain Measurements on the Stimulated Raman Emission in LiquidO2andN2

Abstract
In liquid O2 and N2 the threshold for stimulated Raman emission is found to be much lower than for other nonlinear processes. Thus it is possible to make reliable measurements of the intensity of Raman emission over a large range of incident laser power by using a simple longitudinal geometry. Several distinct regions of emission were investigated, including normal Raman scattering, exponential gain, onset of oscillation, and saturation. There is good agreement with theory.