Small signal gain and saturation intensity of 00° 1-[10°0, 02°0]I and IIvibrational band transitions in sealed-off CO2isotope lasers

Effects due to Fermi resonance play a major role in determining the very significant variations of gain in the various CO2isotopes. We have measured the small signal gain coefficients and saturation parameters for five transitions ( ) in each of the four rotational branches of the I and IIvibrational bands using sealed-off TEMooqmode oscillators and amplifiers. Isotopic species of pure¹²C¹⁶O2,¹²C¹⁸O2,¹³C¹⁶O2,¹³C¹⁸O2, and¹⁴C¹⁶O2were measured with⁴He-¹⁴N2-Xe gas additives under identical conditions. Substitutions of either¹⁵N2or¹³C¹⁶O instead of¹⁴N2were also tried. The results obtained may serve as guidelines in the design of sealed-off CO2lasers and amplifiers.