Realization and investigation of relative experimental parameter of coherent population trapping frequency standard

It is desirable for an atomic frequency standard that clock transition signal is of both high SIN rate and narrow line-width. While for a passive coherent population trapping (CPT) frequency standard, increasing SIN rate is at the expense of enwidened lidnewidth, therefore it is crucial to choose a proper combination of SIN rate and linewidth. The present paper presents the experimental results of our systematically study on the relations between clock transition signal and parameters such as temperature and laser intensity with an optical table top CPT frequency standard. The obtained results provide us the criterion of choosing the combination of SIN rate and lidnewidth. The paper also presents experimental study results of de-coherent effect caused by unperfect circular polarization laser. Those experimental results were the good reference in the realization of CPT frequency standard, and they are also the general reference to CPT phenomenon and CPT frequency standard studies.