Characterization of the modulation transfer spectroscopy method by means of He-Ne lasers and I-127(2) absorption lines at lambda=612 nm

An experimental characterization is presented of sub-Doppler modulation transfer spectroscopy using He-Ne lasers and rovibronic transitions of the iodine molecule at the wavelength of 612 nm. With this technique, the realized optical frequency standard shows a minimum stability value of 6.2 x 10(-13) in 1000 s of integration time, and an estimated reproducibility of 7 kHz (1.6 x 10(-11)). The hyperfine spectroscopy of the recommended transition 9-2, R(47) was also carried out using this method. Finally, the performance of the optical frequency standard and the hyperfine spectroscopy results are compared with those obtained using the frequency modulation spectroscopy technique.