Quantum hacking: Experimental demonstration of time-shift attack against practical quantum-key-distribution systems

作     者：Yi Zhao Chi-Hang Fred Fung Bing Qi Christine Chen Hoi-Kwong Lo 

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 A》 (物理学评论A辑：原子、分子和光学物理学)

年 卷 期：2008年第78卷第4期

页      面：042333-042333页

核心收录：

学科分类：070207[理学-光学] 07[理学] 08[工学] 0803[工学-光学工程] 0702[理学-物理学] 

主　　题：Optical fibers 

摘      要：Quantum-key-distribution (QKD) systems can send quantum signals over more than 100km standard optical fiber and are widely believed to be secure. Here, we show experimentally a technologically feasible attack—namely, the time-shift attack—against a commercial QKD system. Our result shows that, contrary to popular belief, an eavesdropper, Eve, has a non-negligible probability (∼4%) to break the security of the system. Eve’s success is due to the well-known detection efficiency loophole in the experimental testing of Bell’s inequalities. Therefore, the detection efficiency loophole plays a key role not only in fundamental physics, but also in technological applications such as QKD systems.