自由空间量子通信系统研究

Study of quantum communication systems used for free space

提出了一种用于自由空间的量子通信实验系统.该系统由两个子系统组成,分别使用衰减激光作为单光子源和纠缠光子对作为光源,可以分别研究单光子脉冲系统与纠缠光子对系统的大气传输特性,并进行了两种自由空间量子通信方式的性能对比分析.结果表明,低层大气对量子通信的影响较大,单光子脉冲系统的量子密钥传输率较高.

An experimental system of quantum communication that operated for free space is presented. This system is composed of two subsystems, which use attenuated laser or entangled photon pairs as the photon source, respectively. It can be used for experimental investigation in atmospheric characteristics of the system using a single photon source or entangled photon pairs, respectively, along with a comparison of characteristics between the two systems. The results show that the atmosphere in the lower layer plays an important role in affecting the quantum communication, and that the efficiency of the quantum key distribution is higher in the system using a single photon source.