Theoretical and experimental studies of a multiline TEA CO2 laser with hot CO2 as an intracavity absorber

The multiline behavior of a ballast resistance helical TEA CO2 laser incorporating hot CO2 as an intracavity absorber has been studied. Simultaneous laser oscillation on P(16), P(18), and P(20) lines of 10.6 microns has been obtained reliably. A rate equation model has been developed for the hot CO2 absorber and is incorporated with the model for the multiline TEA CO2 laser for calculating laser intensities on P(16), P(18), P(20), and P(22) lines of the 10.6 micron band in the presence of the absorber. The theoretical calculations agree quite well with the experimental observations. These studies show that a hot CO2 column of proper length and temperature inside a TEA CO2 laser cavity can produce simultaneous laser oscillation on at least three rotational lines P(16), P(18), and P(20) of the 10.6 micron band with almost equal intensity.