AI 中文总结
该研究开发了基于原子参考低噪声激光架构的双法拉第激光抽运铯束钟，实现$7.7\times 10^{-13}/\sqrt{τ}$的频率稳定度，为可部署精密授时等提供高性能频率参考。
AI 中文摘要
小型铯束钟是可部署授时系统的主要频率参考，但其短期频率稳定度的进一步提升受限于钟信号信噪比（SNR）。尽管双激光光抽运可提高有效原子利用率，但长期以来，激光诱导的频幅噪声转换限制了可实现的钟信噪比。本文展示了一种紧凑型双法拉第激光抽运（DFP）铯（Cs）束钟，该钟由低频噪声的原子参考激光架构实现。腔内法拉第反常色散光学滤波器可固有匹配Cs D₂共振，而调制转移光谱技术可抑制频率噪声与漂移。所得激光系统支持可靠的一键式操作，其洛伦兹线宽为2.12 kHz。该DFP铯束钟在1 Hz带宽内实现了46365的钟信噪比，分数艾伦偏差为$7.7\times 10^{-13}/\sqrt{τ}$，在10000 s时的阿达马偏差达$7.7\times 10^{-15}$。本研究将紧凑型铯束钟的分数频率稳定度推进至$10^{-13}/\sqrt{τ}$范围，为可现场部署的精密授时、导航与同步应用提供高性能Cs频率参考的实现路径。
英文摘要
Compact cesium beam clocks are major frequency references for deployable timing systems. However, further improvement of their short-term frequency stability is limited by the clock signal-to-noise ratio (SNR). Although two-laser optical pumping can increase the effective atomic utilization, the achievable clock SNR has long been limited by laser-induced frequency-to-amplitude noise conversion. Here, we demonstrate a compact dual-Faraday-laser-pumped (DFP) Cs beam clock enabled by a low-frequency-noise atom-referenced laser architecture. The intracavity Faraday anomalous dispersion optical filter provides inherent alignment to the Cs D$_2$ resonances, while modulation transfer spectroscopy offers suppressed frequency noise and drift. The resulting laser system supports robust turnkey operation with a Lorentzian linewidth of 2.12 kHz. The DFP Cs clock achieves a clock SNR of 46,365 in a 1-Hz bandwidth and a fractional Allan deviation of $7.7\times 10^{-13}/\sqrtτ$ , with Hadamard deviation reaching $7.7\times 10^{-15}$ at 10,000 s. This work pushes the fractional frequency stability of a compact Cs beam clock into the $10^{-13}/\sqrtτ$ regime, providing a pathway toward high-performance Cs frequency references for field-deployable precision timing, navigation, and synchronization.
Comments12 pages, 5 figures
