Amplification of continuously tunable signals in high-pressure CO2 amplifiers

An investigation was made of the emission of high-power continuously tunable signals in a CO₂ laser stage consisting of a master oscillator and an amplifier. The active medium in the oscillator and the amplifier was excited by an electric discharge sustained by an electron beam of 1 μsec duration with a current density of 3 A/cm². The pressure of the CO₂:N₂ = 1:1 active medium in the master oscillator was kept at 6.5 atm and that in the amplifier was varied between 1 and 6 atm. It was found that when signals were amplified under similar conditions at frequencies corresponding to the peak of the P₁₈ line and to the dip between the P₁₈ and P₁₆ lines of the 00°1–10°0 transition, the radiation energy changed no less than twofold as a result of a single passage through the amplifier. Moreover, it was found that the pressure in the amplifier could be reduced considerably compared with that of the active medium in the master oscillator whilst retaining continuous frequency tuning, which meant that the requirements on the excitation system could be reduced and the efficiency of the amplifier could be enhanced.