Simple security proofs for continuous variable quantum key distribution with intensity fluctuating sources

作     者：Li, Chenyang Qian, Li Lo, Hoi-Kwong 

作者机构：Center for Quantum Information and Quantum Control Department of Electrical & Computer Engineering University of Toronto TorontoM5S 3G4 Canada Department of Physics The University of Hong Kong Hong Kong Department of Physics University of Toronto TorontoM5S 3G4 Canada 

出 版 物：《arXiv》 (arXiv)

年 卷 期：2019年

核心收录：

主　　题：Quantum cryptography 

摘      要：Despite tremendous theoretical and experimental progress in continuous variable (CV) quantum key distribution (QKD), the security has not been rigorously established for most current continuous variable quantum key distribution systems that have imperfections. Among these imperfections, intensity fluctuation is one of the principal problem affecting security. In this paper, we provide simple security proofs for continuous variable quantum key distribution systems with intensity fluctuating sources. Specifically, depending on device assumptions in the source, the imperfect systems are divided into two general cases for security proofs. In the most conservative case, we prove the security based on the tagging idea, which is a main technique for the security proof of discrete variable quantum key distribution. Our proofs are simple to implement without any hardware adjustment for current continuous variable quantum key distribution systems. Also, we show that our proofs are able to provide secure secret keys in the finite-size scenario. Copyright © 2019, The Authors. All rights reserved.