Abstract
Optical frequency comb (OFC) and stabilized lasers play important roles in the development of atom and molecule physics, metrology, communication systems and optical clock. In the past, to get frequency stable light source lasers are stabilized to certain atomic or molecular transitions. But the frequency needs to be calibrated by the complicated harmonic chain which links the frequency standard from GHz to THz region. With the realization of optical frequency comb, now we can easily measure the absolute frequency from UV to IR region. In this thesis, we represent two kinds of stabilized laser systems. One is 532 nm iodine stabilized laser by the method of modulation transfer spectroscopy (MTS). MTS provides nearly zero background baseline and frequency unmodulated laser source. The other is 822 nm cesium stabilized by the means of two photon spectroscopy. It provides Doppler free line-width to get precise resonant frequency. We measure the absolute frequencies of both laser systems by our OFC system. We measure the hyperfine component a10 of iodine ro-vibrational transition R(56) 32-0. Its signal to noise ratio (S/N) is 300. Our measured absolute frequency is only 2 kHz below the value recommended by CIPM. The absolute frequencies of cesium 6S1/2 to 8 S1/2 hyperfine transitions are also measured. The S/N ratio of the observed two photon spectrum is 1800 (integration = 10 ms). Our results on absolute frequencies are ~ 20 kHz below Hänsch’s group. However, the hyperfine splitting between F3→F3 and F4→F4 two photon transitions agrees with Hänsch’s group very well.