488nm泵浦的自发参量下转换特性研究  

Research on spontaneous parametric down⁃conversion characteristics by 488 nm pumped

作　　者：尹琳 李健军 郑小兵 YIN Lin;LI Jianjun;ZHENG Xiaobing(Key Laboratory of Optical Calibration and Characterization,Anhui Institute of Optics and Fine Mechanics,HFIPS,Chinese Academy of Sciences,Hefei 230031,China;University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]中国科学院合肥物质科学研究院安徽光学精密机械研究所,中国科学院通用光学定标与表征技术重点实验室,安徽合肥230031 [2]中国科学技术大学,安徽合肥230026

出　　处：《量子电子学报》2024年第4期638-648,共11页Chinese Journal of Quantum Electronics

基　　金：国家重点研发计划(2022YFB3903102)。

摘　　要：自发参量下转换的光谱、光子数率和时间相关性对宽波段光电探测器定标具有重要意义。本文理论模拟了488 nm连续激光泵浦偏硼酸钡(BBO)晶体的光谱和光子数率的分布,搭建了光谱、光子数率和时间相关性测量的实验系统。基于理论研究,BBO晶体的相位匹配角选择24.3184°,可实现605~2523 nm连续宽波段相关光子制备,光子数率最大值为4.2716×10^(7) s^(-1)。采用CMOS相机和光电倍增管测量相关光子圆环和光子数率,根据波长和探测器响应波段来选择相应的光电探测器,以测量时间相关性。实验测量得到605~1000 nm波段的相关光子光谱,光子数率的实测值与理论值偏差在1个量级内,并观察到710~1560 nm波段的符合峰。实验结果验证了所建立的理论模型的正确性、自发参量下转换过程的宽光谱特性和时间相关性,为实现可见-近红外波段的宽光谱相关光子定标提供了研究基础。The spectrum,photon count rate and time correlation of spontaneous parametric downconversion are of great significance for the broadband photodetector calibration.In the work,the spectrum and photon count rate distribution of 488 nm continuous laser pumped barium metaborate(BBO)crystal are simulated theoretically,and an experimental measurement system of spectrum,photon count rate,and time correlation are set up.Based on the theoretical results,BBO crystal phase-matching angle is selected as 24.3184°,which can achieve 605-2523 nm continuous broadband correlated photon spectral preparation,and the maximum of photon count rate can reach to 4.2716×10^(7) s^(-1).CMOS camera and photomultiplier tube are used to measure the correlated photon ring and photon count rate,and the corresponding photodetector is selected according to the wavelength and detector response band to measure the time correlation.As a result,the correlated photon spectrum of 605-1000 nm is measured,and it is found that the measured photon count rate deviates from the theoretical value by an order of magnitude.Besides,the coincidence peaks are also observed in the range of 710 nm to 1560 nm.The experimental results verify the correctness of the theoretical model and the wide spectral characteristics and time correlation of spontaneous parametric down-conversion process,which provides a research foundation for the realization of the wide spectral correlation photon calibration in the visible-nearinfrared band.

关 键 词：非线性光学 可见-近红外相关光子 自发参量下转换 光子数率 时间相关性 

分 类 号：O437[机械工程—光学工程]