We have developed and characterized a pair of Doppler-free acetylene-stabilized diode laser frequency standards as optical communications references. The Allan deviation σ/f of an individual system reaches a minimum of 4×10-14 at a sampling time of 5000 s, and the long-term lock-point repeatability is found to be 0.4 kHz (one standard uncertainty), corresponding to a fractional uncertainty of 2×10-12 . Using a combination of a frequency chain and a self-referenced femtosecond comb, we have measured the frequency of line P(16) of the ν1+ν3 overtone band of 13C 2H2 to be 194 369 569 385.9 (3.0) kHz. The uncertainty of this number is limited solely by the reproducibility of the standards.
(060.4510) Fiber optics and optical communications : Optical communications
(140.2020) Lasers and laser optics : Diode lasers
(140.5960) Lasers and laser optics : Semiconductor lasers
(300.6260) Spectroscopy : Spectroscopy, diode lasers
(300.6390) Spectroscopy : Spectroscopy, molecular
(300.6460) Spectroscopy : Spectroscopy, saturation
Christopher S. Edwards, Helen S. Margolis, Geoffrey P. Barwood, Stephen N. Lea, Patrick Gill, Guilong Huang, and William R. C. Rowley, "Absolute frequency measurement of a 1.5-µm acetylene standard by use of a combined frequency chain and femtosecond comb," Opt. Lett. 29, 566-568 (2004)