Optically pumped 33-atm CO2 laser

Single nanosecond laser pulses at wavelengths near 10 μm have been obtained by using a pulsed HBr laser to optically pump pure CO2 gas at pressures up to 33 atm in a 1-mm-long optical resonator. At pressures above 17 atm, the laser oscillates on the 10.3-μm R branch rather than on the usual 10.6-μm P branch.