Lasing in 15 atm CO₂ cell optically pumped by a Fe:ZnSe laser

10 µm lasing is studied in a compact CO 2 -He cell pressurized up to 15 atm when optically pumped by ∼50 mJ Fe:ZnSe laser tunable around 4.3 µm. The optimal pump wavelength and partial pressure of for generating pulses are found be ∼4.4 0.75 atm, respectively. Without cavity optimization, the optical-to-optical conversion efficiency reached ∼10% at total 7 atm. gain lifetime measured ∼1 µs pressures above indicating feasibility using high-pressure efficient amplification picosecond pulses.