Study Of High-Resolution Spectroscopy Based On Optical Frequency Comb

The development of quantum theory has promoting the formation of high precision spectroscopy and quantum information science which is based on the laser. In the process of the development of modern physics, the exploration of people for high resolution, high precision and high sensitive of spectroscopy has become driving force of many science and technologies. The advent of optical frequency comb has achieved high precision link between optical frequency and microwave and between different optical frequency stan-dard, and opened up new research field of coherent control in time domain and frequency domain. With the advantage of wide bandwidth, high power and god stability, optical fre-quency comb has widely used in hyperfine transition frequency measurement, the fine structure constants measurement and atomic clocks through which we can deeply study the atomic and molecular physics. In this paper, we have studied the interference spec-troscopy between optical frequency comb and single frequency laser, and the precision spectroscopy of two-photon transition which is based on optical frequency comb. The concrete research content is as follows:1. We obtain the interference spectroscopy between optical frequency comb and sin-gle frequency laser. We studied the relationship between frequency of single-frequency laser and the frequency interval of two interference signals presented an effective method to measure the frequency by comparing our experimental result with theory, whose preci-sion can reach MHz.2. After the frequency comb laser traveled through a rubidium vapor, we obtained the interference spectroscopy between the femtosecond pulse laser and single frequency laser. By recording and analyzing the intensity of the interference signal, we get the full absorp-tion profile. It provides a new method in studying atomic and molecular absorption pro-file.3. The optical frequency comb was utilized to excite the cesium atoms of ground state to 8S and 9S states. The high resolution frequency comb spectroscopy was monitored by detecting 7Pâ†'6S fluorescence for a scan of repetition frequency. We have calculated the absolute frequency of cesium hyperfine transition and hyperfine interaction constant.4. The diode laser and optical frequency comb were combined to excite the rubidium atoms of ground state to the 5D state. The diode laser was used to excite the 5Sâ†'5P tran-sition, and the optical frequency comb to 5Pâ†'5D transition. The two-photon spectroscopy was obtained by detecting 6Pâ†'5S fluorescence at 490nm for a scan of diode laser fre-quency. We have studied the relationship between intensity of laser and intensity and li-newidth of spectroscopy.