激光稳频是影响原子喷泉系统性能的关键技术。提出了一种应用于原子喷泉系统的激光稳频优化方案。该方案将激光冷却过程中采用的移频方法应用到稳频系统中，通过光纤电光调制的方法产生边带，并将频率锁定在边带的饱和吸收峰上。同时应用大光斑饱和吸收模块，改善饱和吸收信号和误差信号的信噪比。利用85Rb原子喷泉系统主光路的探测光，通过1.035 GHz的移频，实现从85Rb饱和吸收峰到87Rb饱和吸收峰的转移锁定，并在85Rb喷泉系统中观测到冷原子云信号。锁定后的信号可实现较长时间的稳定工作。该方案通过控制电光调制频率，还有望实现激光冷却实验范围内的任意频率锁定，具有重要的应用价值。

原子喷泉钟是具有重要应用价值的冷原子装置,紧凑型光学系统设计是研制可搬运冷原子喷泉钟的关键技术之一。介绍了一种以通用铝型材搭建的网格化光学平台,并基于此平台实现了 85Rb喷泉钟紧凑型光路。通过仿真,证明了该型材网格平台在二维方向均具有较好的力学性能。在该平台上,设计并搭建了四倍频移、注入锁定放大、冷却光路、再泵浦光路和探测光路等单元模块,满足了喷泉钟的所有要求。该网格平台面积为50 cm×50 cm,高度为2.5~3 cm。该光路实现了8个月以上的持续运行,功率的起伏小于5%。基于该紧凑型光学系统,完成了后续的 85Rb喷泉钟的物理实验和微波实验。

The environmental perturbation on atoms is a key factor restricting the performance of atomic frequency standards, especially in the long-term scale. In this Letter, we perform a real-time noise distinguish (RTND) to an atomic clock to decrease the uncertainty of the atomic clock beyond the level that is attained by the current controlling method. In RTND, the related parameters of the clock are monitored in real time by using the calibrated sensors, and their effects on the clock frequency are calculated. By subtracting the effects from the error signal, the local oscillator is treated as equivalently locked to the unperturbed atomic levels. In order to perform quantitative tests, we engineer time-varying noise much larger than the intrinsic noise in our fountain atomic clock. By using RTND, the influences of the added noises are detected and subtracted precisely from the error signals before feeding back to the reference oscillator. The result shows that the statistical uncertainty of our fountain clock is improved by an order of magnitude to 2×10?15. Besides, the frequency offset introduced by the noise is also corrected, while the systematic uncertainty is unaffected.