Investigation On High Resolution Two-photon Transition Spectroscopy Of Rubidium Atom

Precision spectroscopy is one of the important methods of revealing the laws of microscopic world and discovering the internal structure of matter in the development of modern physics.The relentless pursuit of spectral resolution and sensitivity has become the main driver of technological breakthroughs.The invention of laser has been greatly improved the detection sensitivity,spectral resolution,temporal resolution,spatial resolution of the spectral analysis process,and also extended the research on the traditional spectrum to the fields of precision measurement and ultrafast dynamics.Optical frequency combs combined the precision optical frequency measurement with ultrafast optical,facilitates the development of precision spectroscopy,and makes the high-precision quantum control atomic molecules to be possible.In this paper,the optimal transition of two-photon is achieved by the interaction of laser(narrow linewidth continuous laser and optical frequency comb)with the atoms,and the relevant information of high excited state of rubidium atom is obtained.The main contents are listed as follows:1.The 5S-5P-5D two-photon transition of rubidium atom was realized by the lasers with the wavelengths of 780 nm and 776 nm,respectively.The 87 Rb 5S1/2(F=2)-5D5/2,85 Rb 5S1/2(F=3)-5D5/2,85 Rb 5S1/2(F=2)-5D5/2 and 87 Rb 5S1/2(F=1)-5D5/2 two-photon spectrum were obtained.The relationship of the 420 nm fluorescence intensity with the experimental parameters was studied in detail.2.The diffraction pattern of rubidium atoms in the optical lattice was realized by 5S-5P-5D two-photon transition,and a clear diffraction pattern was obtained.The influence of frequency detuning on the diffraction patterns was researched in detail.This work is of great significance for studying Parity-time symmetry in atomic ensemble.3.Rubidium 5S-5P-5D high resolution two-photon transition spectroscopy was realized by using the optical frequency comb and narrow linewidth continuous laser,the Doppler effect was effectively overcome.The influence of rubidium atom temperature and continuous laser power on the two-photon spectroscopy was systematically studied.This work provides a powerful means for establishing a highly stable optical frequency standard.