Stimulated Inelastic Resonance Fluorescence in an Optically Thick Medium

A non-resonant stepwise optical wave travelling through an ensemble of two-level systems is shown to be accompanied by a resonant optical pulse which is continuously amplified and shortened during the propagation. The sample excitation promoted by this stimulated light is calculated in the limit where the frequency offset is much larger than the linewidth (including the saturation broadening) and is shown to be much below previous estimations and dramatically affected by the rise time of the driving field.