利用终态跃迁实现超小型铷钟双共振信号增强和线宽压窄

铷原子钟具有体积小、功耗低、可靠性高的特点，是目前应用最广泛的原子钟。铷原子钟的研制主要朝着高性能和小型化两个方向进行。近年来，受高精度时间同步领域的需求牵引，对作为高稳频率源的铷原子钟的体积功耗提出了更高的要求，对其频率稳定度的要求却并没有降低。铷钟稳定度指标与原子信号强度和线宽相关，在现有技术状态下，小尺寸铷泡中存在共振信号弱、线宽展宽严重的问题，难以实现较好的频率稳定度。为提升超小型铷钟稳定度性能，使其能够满足未来军事民生领域的重大需求，本项目拟开展相关方案研究。本项目将探索利用终态跃迁实现超小型铷原子钟稳定度提升的技术方案，选取超精细终态磁子能级间的跃迁作为钟跃迁，增多参与共振跃迁的原子数，消除由于原子自旋交换碰撞造成的谱线展宽，实现原子双共振信号增强和线宽压窄，突破制约超小铷钟稳定度性能提升的技术瓶颈，为实现体积不超过30mL、稳定度指标优于3E-12/√τ的超小型铷钟奠定基础。

Due to its characteristics of small volume, low power consumption and high reliability, rubidium atomic clock has become the most widely used atomic clock. Miniaturization and high performance are the main goal in designing a rubidium atomic clock. In recent years, driven by the demand for high-precision time synchronization, requirements for rubidium atomic clocks as high-stability frequency sources have been higher in terms of volume and power consumption, yet not been reduced of frequency stability. The frequency stability of the rubidium atomic clock is related to intensity and line width of atomic double-resonance signal. It’s hard to obtain strong resonance signal and narrow line width in a small sized bubble, thus make it difficult to achieve high frequency stability. This project intends to improve the stability performance of the ultra-miniaturized rubidium atomic clock, making it have the ability to meet the major needs of the military and civilian fields in the future..This project will explore a solution to improve the frequency stability of ultra-miniaturized rubidium atomic clock based on end-state resonances. Magnetic resonance transitions from the “end” sublevels of maximum or minimum spin instead of the conventional 0-0 transition is selected as the clock transition. The end resonances have much stronger signals and can decrease collisional spin-exchange broadening, resulting in a higher signal-to-noise ratio and a narrower line width .This will bring revolutionary changes to the development of ultra-miniaturized rubidium atomic clock technology and lay the foundation for the realization of an ultra- miniaturized rubidium atomic clock which stability can reach a level of 3E-12/√τ with a volume of 30mL.