FPGA在319nm紫外单频激光系统锁频中的应用  

Application of FPGAs in Frequency Locking of the 319 nm Ultra-Violet Single-Frequency Laser System

作　　者：苏雯静 卫怡荣 侯晓凯 王越伟 何军[1,2] 王军民 SU Wenjing;WEI Yirong;HOU Xiaokai;WANG Yuewei;HE Jun;WANG Junmin(State Key Laboratory of Quantum Optics Technologies and Devices,and Institute of Opto-Electronics,Shanxi University,Taiyuan,030006;Collaborative Innovation Center of Extreme Optics,Shanxi University,Taiyuan,030006)

机构地区：[1]山西大学光电研究所,光量子技术与器件全国重点实验室,山西太原030006 [2]山西大学,极端光学协同创新中心,山西太原030006

出　　处：《量子光学学报》2025年第1期106-116,共11页Journal of Quantum Optics

基　　金：国家自然科学基金(12474483);山西省基础研究计划(202403021211013);国家重点研发计划课题(2021YFA1402002);山西省“1331工程”提质增效建设计划(2022-07-01)。

摘　　要：窄线宽、可连续调谐的319 nm紫外单频激光系统对铯原子的单步里德堡激发有重要意义。以高精细度超稳光学腔作为频率参考标准,结合射频位相调制边带PDH(Pound-Drever-Hall)技术、电子学边带技术、无调制HC(Hansch-Couillaud)技术,实现319 nm紫外单频激光系统的频率锁定。然而常规反馈锁定系统存在结构较复杂、体积较庞大、成本较高等缺点,我们通过利用FPGA(Field Programmable Gate Array)代替信号发生器、锁相放大器、PID(Proportional-Integral-Derivative)放大器、示波器等分立设备来实现激光频率的锁定,对常规的反馈锁定系统进行简化和升级;基于Red Pitaya的FPGA板卡,利用射频位相调制边带PDH技术以及电子学边带技术对基频光进行锁定,并对射频位相调制边带PDH技术和无调制HC技术对四镜环形倍频腔的锁频效果进行了比较。FPGA的应用,在实验操作中不仅能够显著地降低成本、简化实验系统,并且充分节约使用空间,带来极大便利,有着较高的集成度、高度的灵活性、良好的稳定性。Objective The narrow-linewidth,continuously tunable single-frequency 319 nm ultra-violet laser system is of great significance for the single-step Rydberg excitation of cesium atoms.The use of high-precision ultra-stable optical cavity,combined with PDH(Pound-Drever-Hall)frequency stabilization technology,electronic sideband frequency stabilization technology,and HC(Hansch-Couillaud)frequency stabilization technology,which realize the frequency locking of the single-frequency ultraviolet laser system.However,the structure of the conventional feedback locking system is much complex,the cost is higher,the volume is larger,and the whole process requires more seperated instruments.Therefore,FPGA(Field Programmable Gate Array)is used to simplify and upgrade conventional feedback locking systems.Methods FPFA has the advantages of low energy consumption,high efficiency,high flexibility,high integration,high stability.programmability,and it has application prospects in the whole scientific research,especially in the field of quantum optics and atomic physics.Frequency sweeping,modulation and demodulation,feedback control and monitoring through the Red Pitaya board can make the whole laser system simple.FPGA can not only greatly reduce the cost in the experiment,but also fully save the space,bring great convenience,and have high integration,high flexibility,high stability and simple operation.Results and Discussions Based on the Red Pitaya's FPGA board,the laser frequency is locked by using PDH frequency stabilization technology,electronic sideband frequency stabilization technology,and HC frequency stabilization technology.The frequency locking effect of PDH frequency stabilization technology and HC frequency stabilization technology of the four-mirror frequency-doubling ring cavity is compared,the frequency fluctuation after PDH locking is±0.425 MHz within 10 minutes,and the frequency fluctuation after HC locking is±0.61 MHz within 10 minutes,the locking effect of PDH scheme is better,and it has a wider range of conti

关 键 词：现场可编程门阵列(FPGA) 319nm单频紫外激光 PDH锁定 电子学边带锁定 HC锁定 

分 类 号：O435.5[机械工程—光学工程] TN914.5[理学—光学]