一种设定POP铷原子钟气泡工作温度的方法研究

A method for setting the operating temperature of the bubble of POP rubidium atomic clock

原子气泡工作温度以不同的方式影响POP铷原子钟短期稳定度和长期稳定度,短期稳定度最优工作温度点与长期稳定度最优工作温度点越接近,原子钟稳定度越好。基于POP铷原子钟建立了温度-碰撞频移曲线测量系统,以微波探测法为例,介绍了一种高效简便的零温度系数点测量方法,测量了几种不同比例氮气和氩气的缓冲气体组合的原子气泡零温度系数点,给出了满足POP原子钟10-15长期Allan方差所需的控温精度,并分析了设计值与实验拐点位置差别的原因。最后,分析POPRamsey信号大小随温度的变化曲线,找到了符合短期稳定度的最优工作温度。

The working temperature of atomic bubble affects both the short-term stability and long-term stability of the POP rubidium atomic clock. The closer the optimal operating temperature of the short-term stability is to that of long-term stability, the better the stability of the atomic clock is. Based on the POP rubidium atomic clock, a temperature-collision frequency shift curve measurement system was established. Taking the microwave detection method as an example, an efficient and simple inflection point measurement method was introduced. We have measured the temperature inflection point of atomic bubble with different ratios of nitrogen and argon buffer gases. The required temperature control accuracy for the long-term Allan’s variance of the 10^-15 POP atomic clock is given, and the reason for the difference between the design and experimental inflection points was analyzed. Finally, combined with the curve of signal variation with temperature, an optimal operating temperature that meets the short-term stability is found.