Absolute frequency measurement of 12C16O2 laser lines with a femtosecond laser comb and new determination of the 12C16O2 molecular constants and frequency grid

• Published in: Journal of molecular spectroscopy Vol. 228; no. 1; pp. 206 - 212
• Main Authors: Amy-Klein, A., Vigué, H., Chardonnet, C.
• Format: Journal Article
• Language: English
• Published: Elsevier 01.11.2004
• Subjects: Physics; Quantum Physics; molecular constants; CO2; saturated absorption; absolute frequency measurement
• ISSN: 0022-2852; 1096-083X
• DOI: 10.1016/j.jms.2004.07.005

Absolute frequency measurements of a CO2 laser stabilized on saturated absorption resonances of CO2 laser lines are reported. They were performed using a femtosecond-laser frequency comb generator and two laser diodes at 852 nm and 782 nm as intermediate oscillators, with their frequency difference phase-locked to the CO2 laser. 20 12C16O2 laser lines in the P and R bands at 9 µm were measured with a relative uncertainty of a few 10-12 limited by the CO2 frequency reproducibility. A new determination of the CO2 molecular constants was obtained from these data and previous measurements in the 10 µm band. The CO2 frequency grid was also calculated, with an improvement of two orders of magnitude compared to the previous grid of Maki et al [A.G. Maki, C.C. Chou, K. Evenson, L.R. Zink and J.T. Shy, J. Mol. Spectrosc. 167, (1994) 211-224].