读光强度对光与原子纠缠源读出效率及纠缠质量的影响  

The Influence of Read Field Intensity on The Retrieval Efficiency and Entanglement Quality of Atom-Photon Entanglement Source

作　　者：张常睿 王圣智 徐忠孝[1,2] 李淑静 王海[1,2] ZHANG Chang-rui;WANG Sheng-zhi;XU Zhong-xiao;LI Shu-jing;WANG Hai(State Key of Laboratory of Quantum Optics and Quantum Optics Device;Collaborative Innovation Center of Extreme Optics,Institute of Opto-Electronics,ShanxiUniversity,Taiyuan 030006,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,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》2018年第3期303-308,共6页Journal of Quantum Optics

基　　金：国家重点研发计划(2016YFA0301402);国家自然科学基金(11475109;11274211;11604191);山西省“1331工程”重点学科建设计划经费资助;山西省应用基础研究计划(201601D202007)

摘　　要：在87 Rb冷原子系综中,利用自发Raman散射过程,实现了光与原子的纠缠。测量了读光功率对光与原子纠缠质量以及读出效率的影响,结果显示：anti-Stokes光子恢复效率与Bell参数S值随着读光功率的增加均呈现先上升后下降的趋势;其中读光功率为5 mW时anti-Stokes光子恢复效率达到17.8%,Bell参数S值达到2.5。我们选取读光功率3.5mW时测量了Bell参数S值随存储时间的变化,结果显示：存储时间为3μs时,Bell参数S值达到2.5;在存储时间为9μs的时候S参数的测量值仍然大于2,证明产生的光与原子的纠缠可以保持9μs以上。本文的研究结果为产生高质量的光与原子量子纠缠提供了实验基础。The photon-atom entanglement is realized by spontaneous Raman scattering process in the 87 Rb cold atom ensemble.Based on this,the influence of the read field intensity on the entanglement quality is measured.The results show that,when the power of read field is 5 mW,the retrieval efficiency of antiStokes photon can reach 17.8%,and the value of Bell parameter Scan reach 2.5.We have measured the change of Bell parameter S with the storage time when the read field intensity is 3.5 mW.The result show that the value of Bell parameter Sreaches 2.5 when the storage time is 3μs and the value of Sparameter is still greater than 2 when the storage time is 9μs,which proves that the photon-atom entanglement we have generated can be maintained over 9 μs.The results of this paper provide an experimental basis for the generation of high quality quantum entanglement of photon-atom entanglement.

关 键 词：冷原子系综 自发拉曼散射 光与原子纠缠 

分 类 号：O431.2[机械工程—光学工程]