Radiation Of Ne Atoms And CO Molecules In Intense Laser Fields

The interaction of intense laser fields with atoms and molecules always is one of the hot topics in the research of atomic and molecular physics.The quantum state resolution is achieved in the measurement of the spectrum,which is a good supplement to particle detection methods.The study of the radiation characteristics of atoms and molecules in the strong laser fields is helpful to understand the physical processes such as strong field ionization and excitation,and can also promote the research of air lasers and new extreme ultraviolet lasers.In this paper,the radiation characteristics of Ne atoms and CO molecules in the 800nm 50fs intense laser field were studied with the method of fluorescence spectrum,and the following conclusions were obtained:1)We studied the radiation characteristics of Ne atoms in the femtosecond laser fields.In the experiment,we observed the fluorescence spectrum of Ne atoms,and also measured the time-domain characteristics of different spectral lines and their dependence on the laser parameters(such as laser intensity,ellipticity).At the same time,we compared the results of the fluorescence spectrum with the measurement of the charged particle detection.Our results confirmed the radiation produced by the transition to 3p or 3s state from the excited states with principal quantum number(n=3?5),which were produced in the relaxation the directly populated Rydberg states.Our results show that the Rydberg states populated by the strong-field RSE have a larger angular quantum number l,which is consistent with the prediction of the latest quantum orbit calculations.2)We investigated the fluorescence emission spectrum of the ionized CO molecule in the strong laser fields,and the emission spectrum of CO molecule ions A~2?_i-X~2?~+transition was identified,this proved that HOMO-1 orbital participated in the strong field ionization of CO molecule.We obtained the vibration population of A~2?_ielectron state of the CO molecules;it is found that the Vibration population of strong field ionization is different from that of weak field ionization.At the same time,we measured the vibration population under different laser intensities and ellipticities.