Molecular infrared laser with Br*→CO2 electronic–vibrational energy transfer as the pump mechanism

Results are presented of an experimental investigation of an infrared laser utilizing IBr–CO₂ and Br₂–CO₂ mixtures pumped by electronic-vibrational coUisional excitation transfer from electronically excited Br*(4²P_1/2) atoms to Raman vibrational states [(10⁰1)–(02⁰1)] of the CO₂ molecule. It is shown that, under conditions of broad-band flash photolysis, the IBr molecule is a more efficient supplier of Br*(4²P_1/2) atoms than Br₂·As a result, simultaneous three-frequency laser action at wavelengths of 2.7 μ (4²P_1/2→4²P_3/2 transition in atomic bromine), 4.3, and 10.6 μ (vibrational–rotational transitions in the CO₂ molecule) was obtained from an IBr–CO₂ mixture. On the other hand, laser action was only obtained at 10.6 μ from a Br₂–CO₂ mixture. A qualitative laser model developed showed satisfactory agreement with the experiment.