连续变量量子通信的研究与展望

Research and prospect on continuous variable quantum communication

基于量子力学原理的量子通信具有绝对安全特性,能够满足信息时代的要求,因此,受到了学术界、信息产业界以及各国政府的广泛关注。连续变量量子通信是针对离散变量量子通信中所面临的探测困难、密钥率低、缺乏简单可靠的单光子源等瓶颈而提出的一种新的量子保密通信方案。在介绍连续变量量子通信的基本原理基础上,分别介绍近年来基于压缩态、相干态以及纠缠态的连续变量量子密钥分配(CVQKD)的研究现状,讨论了目前的几类QKD协议中存在的问题以及面临的挑战。

Based on the principle of quantum mechanics, quantum communication has absolute security characters, which could satisfy the trend of information times, therefore the concern is extensive attracted by the academia, the information industry and the governments. Continuous variable quantum communication, as a new scheme of quan- tum secret communication,aims at the bottlenecks existing in the discrete variable quantum communication, such as the difficulty of detection,low secret key rate and the lack of a simple and reliable single photon source. In this pa- per, the elemental principle of continuous variable quantum communication is introduced firstly. Then the research progress of continuous variable quantum key distribution （CVQKD） based on squeezed state ,coherent state and en- tanglement state in recent years are shown, respectively. Finally, the problems and challenges of several kinds of QKD protocol at present are discussed.