We have measured the absolute optical frequencies of 90 rovibrational lines of the 12C2/sub>H2/sub> and 13C2/sub>H2/sub> 1.5-μm bands. Using an optical frequency comb generator, we could precisely measure the relative frequencies between two lasers stabilized on the saturation dip of the rovibrational lines up to 2 THz apart. The absolute frequencies were determined with respect to the Rb two-photon transition at 0.778 μm with a HCN rovibration line at 1.556 μm used as an intermediate reference. This measurement provides an accurate frequency atlas of acetylene 1.5-μm bands with an uncertainty of ~10−9.
© 1996 Optical Society of America
K. Nakagawa, M. de Labachelerie, Y. Awaji, and M. Kourogi, "Accurate optical frequency atlas of the 1.5-um bands of acetylene," J. Opt. Soc. Am. B 13, 2708-2714 (1996)