Status and Prospects of Optically Pumped High-pressure CO2 Amplifiers

High-pressure 10–20 atm compact optically pumped CO2 lasers can become an important technology for generating GW and TW peak power subpicosecond pulses in the Long-wave Infrared (LWIR) range. We critically review all possible ways to efficiently optically pump CO2 molecule in order to obtain inversion of population in the 10 μm 001–100 channel. For the most optimal pumping in the 000–001 channel around 4.3 μm, we present a summary of our experimental and numerical results using a 4.3 μm Fe:ZnSe laser system for pumping. Lasing at ~10 μm in a palm-size CO2-He filled cell was demonstrated at a total pressure up to 15 atm. Further steps in the program aimed to amplify 03-0.5 ps LWIR pulses to a few GW level in optically pumped active medium containing multiple CO2 isotopes are discussed.