高性能被动型CPT原子钟发展趋势

Development Trend of High Performance Passive CPT Atomic Clock

运用单一圆偏光构型达成CPT态会产生极化暗态使得CPT信号对比度较低。因此,传统的CPT原子钟频率稳定度指标不高。为提高CPT信号对比度从而提高CPT原子钟性能,各种消除极化暗态的方案不断被提出并获得研究,这些方案可以根据所使用的激光偏振状态及其产生方式分为平行线偏振光构型、相位延迟的σ^(+)-σ^(-)构型、推挽光泵浦构型、垂直线偏振光构型、偏振调制构型。基于这些方案的原理和发展水平,对比分析各个方案的优缺点和改进方案,可探索不同需求条件下高性能原子钟新的发展方向。

The use of a single circularly polarized light configuration to achieve a CPT state will generate a polarized dark state,resulting in a lower contrast of the CPT signal.Therefore,the frequency stability index of traditional CPT atomic clocks is not high.In order to improve the contrast of CPT signals and improve the performance of CPT atomic clocks,various schemes for eliminating polarized dark states have been proposed and studied.These schemes can be divided into parallel line polarized light configurations and phase delayed configurations based on the polarization state and generation method of the laser used σ~+-σ~-Configuration,push-pull pump configuration,vertically polarized light configuration,polarization modulation configuration.Based on the principles and development level of these schemes,a comparative analysis of their advantages,disadvantages,and improvement plans can be conducted to explore new development directions for high-performance atomic clocks under different demand conditions.