用于铯原子里德伯态激发的509nm波长脉冲激光系统  

A 509 nm pulsed laser system for Rydberg excitation of cesium atoms

作　　者：刘瑶[1] 何军[1,2] 苏楠[1] 蔡婷 刘智慧 刁文婷[3] 王军民[1,2] Liu Yao;He Jun;Su Nan;Cai Ting;Liu Zhi-Hui;Diao Wen-Ting;Wang Jun-Min(State Key Laboratory of Quantum Optics and Quantum Optics Devices,Institute of Opto-Electronics,Shanxi University,Taiyuan 030006,China;Collaborative Innovation Center of Extreme Optics,Shanxi University,Taiyuan 030006,China;National Key Laboratory of Science and Technology on Space Microwave,China Academy of Space Technology(Xi’an),Xi’an 710000,China)

机构地区：[1]山西大学光电研究所,量子光学与光量子器件国家重点实验室,太原030006 [2]山西大学,省部共建极端光学协同创新中心,太原030006 [3]中国空间技术研究院西安分院,空间微波技术国家级重点实验室,西安710000

出　　处：《物理学报》2023年第6期38-43,共6页Acta Physica Sinica

基　　金：国家重点研发计划(批准号:2021YFA1402002);国家自然科学基金(批准号:61875111,62071376);山西省“1331工程”重点项目资助的课题.

摘　　要：介绍了一种用于里德伯原子激发的纳秒脉冲激光系统.实验利用两个kHz线宽的1018 nm连续激光器作为种子源,通过两个20GHz带宽的光纤调制器产生时间分离的脉冲激光;脉冲激光经掺镱光纤放大器后输出峰值功率约4600 W,单次穿过PPLN(周期极化铌酸锂)晶体倍频获得509 nm脉冲激光,典型脉冲激光峰值功率约173W.该激光系统单路输出脉冲重复频率在300 kHz-100 MHz范围连续可调,脉宽在1-100 ns范围连续可调.该509 nm激光在聚焦条件下可以实现GHz带宽的铯原子里德伯态激发.Single photon source is a non-classical light field with anti-bunching effect,which has a potential applications in the research of fundamental physics problems,quantum precision measurement,quantum communication,quantum computing,etc.The strong interaction between highly excited Rydberg atoms presents an excitation blockade effect.In a dense Rydberg atomic ensemble,the excitation of more than one Rydberg atom within a blockade volume is suppressed,where the interactions of Rydberg atoms shift the atomic states out of resonance with an excitation laser.We consider here the generation of single photon source by using a four-wave mixing scheme in a room-temperature atomic vapor cell.In a homemade micrometer-sized atomic vapor cell,one-dimensional size is smaller than the radius of Rydberg blockade and the other two-dimensional size is limited by the size of focused laser beam.The blockade radius is on the order of a few micrometers,depending on the Rydberg atom states.An excitation blockade effect can be used to realize single photon source in thermal cesium vapor microcells.The micron cesium-cell is used to spatially localize atomic groups,which results in the atomic decoherence time on the order of microseconds or even nanoseconds.This requires a high-power pulsed laser to prepare the Rydberg atomic state at a nanosecond scale.Four-photon excitation schemes with narrow linewidth lasers are also used experimentally.The cesium-Rydberg state can usually be excited by the lasers with optical wavelengths 852 and 509 nm,respectively.The laser system is well-stabilized so that the detuning is small compared with the spontaneous linewidth of Rydberg state,while the laser power and temporal mode need to be specified for ns-time coherence in thermal cesium vapor microcells.The 852 nm laser can be achieved by modulating the continuous laser beam with the help of an electro-optic intensity modulator(EOIM).While this remains a technical challenge for 509 nm laser with ns-laser pulse.There is no EOIM to generate the ns-laser p

关 键 词：里德伯原子 脉冲激光器 非线性频率转换 单光子源 

分 类 号：TN24[电子电信—物理电子学]