用于小型铯原子喷泉钟的紧凑型激光系统  

Compact Laser System for Small Cesium Atomic Fountain Clock

作　　者：金双浩 林平卫[1,3] 茹宁 马彦宁 江文松 罗哉 Jin Shuanghao;Lin Pingwei;Ru Ning;Ma Yanning;Jiang Wensong;Luo Zai(Center for Advanced Measurement Science,National Institute of Metrology,Beijing 100029,China;College of Metrology&Measurement Engineering,China Jiliang University,Hangzhou 310018,Zhejiang,China;Innovation Center for Advanced Traceability Technology,Beijing 102299,China)

机构地区：[1]中国计量科学研究院前沿计量科学中心,北京100029 [2]中国计量大学计量测试工程学院,浙江杭州310018 [3]先进溯源技术创新中心,北京102299

出　　处：《光学学报》2024年第19期241-247,共7页Acta Optica Sinica

基　　金：中央级科研院所基础研究基金重点项目(AKYZD2011-2)。

摘　　要：紧凑而简单的激光系统对于实现小型铯原子喷泉钟至关重要。本文介绍了一种紧凑型激光系统,提供小型铯原子喷泉钟所需的全部激光,其体积不到0.015 m^(3)。通过开环移频法取代双通声光调制器移频方法,实现了激光频率快速且大范围失谐。实验结果表明,频率锁定运行的激光系统在喷泉钟偏振梯度冷却时序到达的瞬间打开锁频环路,控制电压逐渐升高,进而改变激光注入电流,实现了激光频率在2 ms内约150 MHz的变化,并能够在5 ms短时间内重新锁定。激光系统产生的上抛下落冷原子数信号波动控制在10%,为喷泉钟连续运行提供了稳定的基础。Objective The cesium atomic fountain clock is a device that can provide high-precision time and frequency signals by reproducing the SI unit of the second.It is employed in various fields such as quantum precision measurement,satellite positioning and navigation,and geological exploration.With advancements in laser technology and changing application scenarios,the development of cesium atomic fountain clocks has increasingly emphasized compactness,automation,and high reliability.The laser system,being the core component of the cesium atomic fountain clock,traditionally occupies significant space due to spatial light paths and optic components.Larger systems are more susceptible to environmental influences.Therefore,developing compact and highly reliable laser systems is crucial for small cesium atomic fountain clocks.Methods The proposed laser system is composed of three main modules:laser frequency stabilization,laser amplification,and laser beam splitting.In the frequency stabilization and amplification modules,a folded double-sided optical path design is employed to control the volume within 210 mm×210 mm×165 mm.The traditional double-pass acousto-optic modulator(AOM)solution is replaced by an open-loop frequency shifting method,eliminating the need for the AOM and associated components.Moreover,in the laser beam splitting module,an electro-optical modulator with a fiber interface is used for 9 GHz modulation,utilizing the edge frequency light generated by phase modulation as repumping light.This eliminates the need for separate repumping lasers and their complex frequency stabilization paths.These improvements significantly simplify the optical path design.Furthermore,the laser beam splitting adopts an all-fiber beam splitting scheme,further compressing the system’s volume.Results and Discussions The frequency of the distributed feedback(DFB)laser remains locked within 50 ms,with the voltage error signal fluctuating within the±1 V range without any jumps.The central slope of the frequency identification

关 键 词：半导体激光器 激光稳频 激光移频 自动化 小型化 

分 类 号：O4369[机械工程—光学工程]