Improving the spectral purity of single photons by a single-interferometer-coupled microring  

作　　者：Yang Wang Pingyu Zhu Shichuan Xue Yingwen Liu Junjie Wu Xuejun Yang Ping Xu 王洋;朱枰谕;薛诗川;刘英文;吴俊杰;杨学军;徐平(Institute for Quantum Information & State Key Laboratory of High Performance Computing, College of Computer Science and Technology,National University of Defense Technology,Changsha 410013,China)

机构地区：[1]Institute for Quantum Information & State Key Laboratory of High Performance Computing, College of Computer Science and Technology,National University of Defense Technology,Changsha 410013,China

出　　处：《Chinese Physics B》2022年第3期311-315,共5页中国物理B（英文版）

基　　金：Project supported by the National Basic Research Program of China (Grant Nos. 2019YFA0308700 and 2017YFA0303700);the Open Funds from the State Key Laboratory of High Performance Computing of China (HPCL, National University of Defense Technology)。

摘　　要：We experimentally engineer a high-spectral-purity single-photon source using a single-interferometer-coupled silicon microring. By the reconfiguration of the interferometer, different coupling conditions can be obtained, corresponding to different quality factors for the pump and signal/idler. The ratio between the quality factor of the pump and signal/idler ranges from 0.29 to 2.57. By constructing the signal–idler joint spectral intensity, we intuitively demonstrate the spectral correlation of the signal and idler. As the ratio between the quality factor of the pump and signal/idler increases, the spectral correlation of the signal and idler decreases, i.e., the spectral purity of the signal/idler photons increases. Furthermore,time-integrated second-order correlation of the signal photons is measured, giving a value up to 94.95 ± 3.46%. Such high-spectral-purity photons will improve the visibility of quantum interference and facilitate the development of on-chip quantum information processing.

关 键 词：spectral-purity MICRORING asymmetric Mach–Zehnder interferometer 

分 类 号：O431.2[机械工程—光学工程]