It is shown that a high-gain CO2-laser chain made of rapidly excited high-pressure amplifiers can be operated without interface isolators. Saturable absorbers are then used only to prevent amplification of front-end leakage and are required to absorb solely at the working frequencies. CH3OH, CH3OD, CH3F, CCI2F2, and HCOOH have been characterized in view of pulse contrast enhancement around 9.4 µm in a multiline multiband laser chain. The optimum pressure, the saturating fluence, the small-signal absorption coefficient, and its ratio over the saturated absorption coefficient are given for many CO2-laser lines.
© 1984 Optical Society of America
Pierre Lavigne and Danny Pascale, "Saturable absorbers for multiband operation of a high-gain short-pulse CO2-laser chain," Appl. Opt. 23, 40-47 (1984)