原子频标要求高信噪比和窄线宽的鉴频信号,但对于被动型相干囚禁态原子频标(CPT频标),改善鉴频信号信噪比以增加线宽为代价,因此选择合适的信噪比和线宽组合是研制CPT原子频标频标的重要环节。文章介绍了用桌面CPT频标系统地研究了鉴频信号与温度、光强等参数的关系所获得的研究结果,由此获得了合适选取的信噪比与线宽组合的依据。文章还给出了关于光源非理想偏振导致的消相干效应对CPT频标的影响所开展的实验结果。文章所提供的研究结果不仅帮助我们研制成功了CPT频标,而且对于CPT物理现象研究和其他CPT频标的研制也有参考价值。
It is desirable for an atomic frequency standard that clock transition signal is of both high S/N rate and narrow linewidth. 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 S/N 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.