Experimental Quantum Key Distribution with Decoy States

作     者：Yi Zhao Bing Qi Xiongfeng Ma Hoi-Kwong Lo Li Qian 

作者机构：Center for Quantum Information and Quantum Control Department of Physics and Department of Electrical and Computer Engineering University of Toronto Toronto Ontario M5S 3G4 Canada 

出 版 物：《Physical Review Letters》 (Phys Rev Lett)

年 卷 期：2006年第96卷第7期

页      面：070502-070502页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

基　　金：National Science Foundation  NSF  (0086038) 

主　　题：Quantum theory 

摘      要：To increase dramatically the distance and the secure key generation rate of quantum key distribution (QKD), the idea of quantum decoys—signals of different intensities—has recently been proposed. Here, we present the first experimental implementation of decoy state QKD. By making simple modifications to a commercial quantum key distribution system, we show that a secure key generation rate of 165 bit/s, which is 1/4 of the theoretical limit, can be obtained over 15 km of a telecommunication fiber. We also show that with the same experimental parameters, not even a single bit of secure key can be extracted with a non-decoy-state protocol. Compared to building single photon sources, decoy state QKD is a much simpler method for increasing the distance and key generation rate of unconditionally secure QKD.