纠缠光子源的性能模型与实验实现  

Performance model and experimental implementation of entangled photon source

作　　者：王冬阳 吴俊杰[1] 刘英文[1] 杨学军[1] WANG Dong-yang;WU Jun-jie;LIU Ying-wen;YANG Xue-jun(School of Computer,National University of Defense Technology,Changsha 410073,China)

机构地区：[1]国防科技大学计算机学院,湖南长沙410073

出　　处：《计算机工程与科学》2020年第10期1757-1764,共8页Computer Engineering & Science

基　　金：国家自然科学基金(61632021)。

摘　　要：量子计算是高性能计算的前沿研究方向,光子物理体系是量子计算的重要实现途径之一。在光量子计算系统中,纠缠光子源用于生成编码量子信息的光子,其性能直接影响量子比特的数量与质量。系统分析了最常用的纠缠光子源技术——基于自发参量下转换的纠缠光子源,研究了基于I型自发参量下转换纠缠多光子源的纯度、亮度的性能模型,推导出由纠缠双光子获得纠缠多光子的关键条件。同时,利用偏硼酸钡晶体器件设计实现了I型自发参量下转换纠缠双光子源,基本验证了上述性能模型。本文模型与实验结果,为在光量子计算系统中实现更多量子比特提供了理论和技术支撑。Quantum computing is a frontier research field in high performance computing,and photon system is one of the important ways to implement quantum computing.In optical quantum computing,the entangled photon source is used to generate photons to encode quantum information,and its performance affects the quality and quantity of quantum bits directly.This paper systematically studies the entangled photon source based on spontaneous parametric down conversion(SPDC),which is the most popular technique to this aim,analyzes the performance model to study purity and brightness of entangled photons generated by type-I SPDC,and derives the key condition to obtain multi-photon entanglement via two-photon entanglement.Meanwhile,using barium metaborate,this paper realizes two photons entangled based on type-I SPDC,and mainly verifies our performance model.The model and the experiment results provide theoretical and technical support for generating more quantum bits in optical quantum computing system.

关 键 词：光量子计算 自发参量下转换 纠缠光子源 

分 类 号：TP305[自动化与计算机技术—计算机系统结构]