Pulsed electron-beam-controlled carbon monoxide laser amplifiers. I. Amplification of radiation from a CO laser operating in the free-running regime

An experimental investigation was made of pulsed electron-beam-controlled carbon monoxide laser amplifiers. Efficient amplification of radiation pulses from electron-beam-controlled CO lasers operating in the free-running regime was achieved under conditions of spectral and temporal matching between the master oscillator and the laser amplifier. The requirements imposed on the master oscillator and laser amplifier in order to provide such matching were formulated. The spectral properties of a multifrequency signal at the output of a laser amplifier were found to depend on the radiation energy density at its input. The saturation energy of the multifrequency signal of ~ 5 J · cm ^– 2 · amagat^– 1 and the specific output energy from the laser amplifier of ~ 90–100 J · liter^– 1  · amagat^– 1 were greater by a factor of about 5 than the corresponding values in the case of a single-frequency signal. The electrooptic efficiency of the amplifier was found to be ~ 15–20%. The radiation energy at the output of an amplifier with an 8-liter active volume (CO:N₂ = 1:9, N = 0.25 amagat, T ≈ 110 K) reached ~ 230 J.