HIGH-POWER TUNABLE 385-MU-M D2O VAPOR LASER OPTICALLY PUMPED WITH A SINGLE-MODE TUNABLE CO2 TEA LASER

We demonstrate a 2-GHz tunability of the 385-μm stimulated Raman transition of D2O vapor optically pumped by the 9R (22) transition of a tunable single-mode CO2 TEA laser. Power levels of up to 800 kW in 100-nsec pulses and conversion efficiency of CO2 laser energy to D2O laser energy at 385 μm of up to 0.4% have been obtained with a D2O oscillator cavity. The TEA CO2 pump laser, which consists of a grating and étalon tuned oscillator followed by an amplifier chain, produced 25-J 100-nsec single-mode pulses and was tunable ±1 GHz around the 9R (22) line center. The present results indicate that tunable single-mode pump lasers are necessary in order to optimize high-power optically pumped laser systems and to produce narrow-linewidth spectral characteristics.