单光子符合探测的研究与应用

发布时间：2018-05-30 01:42

  本文选题：符合测量 + 单光子探测器　； 参考：《聊城大学》2017年硕士论文

【摘要】：符合测量借助电子学的手段将时间相关的脉冲从不同探测器的输出脉冲中选择出来。携带量子信息的单光子可以通过单光子探测器检测,并将此转换为电信号,进而输出,最后通过符合测量和符合计数等措施来获得单光子所携带的信息。单光子符合探测在单光子源的研究、量子操作、多光子干涉、纠缠光子对的判定、单光子干涉的研究、全光量子计算等量子通信与信息领域有着极其重要的应用。对于符合计数,它可以用乘法器与门等分立元件来实现,但是分立元件会给信号带来额外的延迟。近几年,由于基于现场可编程门阵列(FPGA)的迅速发展,FPGA具有更多的门电路,体积更小,成本更低,并且方便随时修改设计直至满足实验要求。越来越多的人选择使用FPGA设计符合计数系统,但是许多系统的设计存在同一个问题:两通道信号到达FPGA引入的路径延迟不一致性而带来符合计数误差。为了解决这一问题,针对外部触发的单光子探测器,我们实验室对脉冲边沿触发型的单光子探测器进行符合计数器的设计,并且验证了合理性。主要内容有以下两个部分:第一:论述了符合测量的基本原理、方法和多种单光子探测器,比较了几种单光子探测器的使用范围。针对外部触发的单光子探测器,设计了双通道符合计数系统。整个符合系统的设计分为了“联合整形”,延迟符合和符合计数三个部分。其中,难点在于“联合整形”的处理,这也是本论文的创新之处。它成功解决了由路径延迟而引起的误差。我们通过QuartusⅡ调用ModelSim-Altera进行仿真,验证了系统的正确性。第二:介绍了单光子源的二阶相关函数。在实验中首次采用了基于掺铒光纤的单光子源,二阶相关函数是评价单光子源的最重要的指标。我们通过符合测量来测得二阶相关函数,以此来评价基于掺铒光纤的单光子源。本论文所设计的符合计数系统和以往的符合计数系统相比具有更好的精确性,能够更加准确地完成单光子探测相关的实验。
[Abstract]:Coincidence measurement selects time-dependent pulses from the output pulses of different detectors by electronic means. A single photon carrying quantum information can be detected by a single photon detector and converted into an electrical signal and then output. Finally, the information carried by a single photon can be obtained by means of coincidence measurement and coincidence counting. Single-photon coincidence detection has important applications in the field of quantum communication and information, such as the study of single photon source, quantum operation, multi-photon interference, determination of entangled photon pair, single-photon interference and all-optical quantum computation. For coincidence counting, it can be implemented by discrete elements such as multipliers and gates, but the discrete elements can cause additional delay to the signal. In recent years, due to the rapid development of FPGA based on Field Programmable Gate Array (FPGA), FPGA has more gate circuits, smaller size, lower cost, and is convenient to modify the design at any time to meet the experimental requirements. More and more people choose to use FPGA to design the coincidence counting system, but many systems have the same problem: the inconsistency of path delay introduced by the two-channel signal arrival FPGA leads to the coincidence counting error. In order to solve this problem, we designed a coincidence counter for the externally triggered single-photon detector in our laboratory, and verified the rationality. The main contents are as follows: first, the basic principle and method of coincidence measurement and several kinds of single-photon detectors are discussed, and the application range of several single-photon detectors is compared. A double channel coincidence counting system is designed for the external triggered single photon detector. The design of the whole coincidence system is divided into three parts: joint shaping, delay coincidence and coincidence counting. Among them, the difficulty lies in the treatment of joint plastic surgery, which is also the innovation of this paper. It successfully solves the error caused by path delay. The correctness of the system is verified by Quartus 鈪，

本文编号：1953370