Observation of Stimulated Anti-Stokes Raman Scattering in Inverted Atomic Iodine

Nonresonant stimulated anti-Stokes Raman scattering from an inverted population in atomic iodine has been observed. The population inversion was achieved by flash photolysis of trifluoromethyliodide. A gain of $e^7$ was measured for a laser probe pulse at the anti-Stokes wavelength passing through the inverted iodine coincident with a laser pump pulse. This result is in good agreement with theoretical predictions.