Applying Gaussian quantum discord to quantum key distribution

Rong Wang, Chun-Mei Zhang, Zhen−Qiang Yin

Xiong Yang, Guo Hui Huang, Mao Fa Fang

Xiaolong, Su

在这份报纸，我们理论上证明光地的 Gaussian 量不一致状态能被用来完成连续变量(CV ) 量钥匙分发(QKD ) 。计算证明那把秘密钥匙能对纠缠 cloner 攻击与一个 Gaussian 量不一致状态被提取。秘密的关键率与与 Gaussian 量不一致状态为 CV QKD 增加量不一致被增加。尽管计算结果用 Gaussian 量不一致指出那秘密的关键率，说在一样的精力水平用挤压的状态和协调状态是比那低的，我们证明 Gaussian 量不一致，没有纠纷的存在，仅仅包含量关联，可以为认识到 CV QKD 提供一个新资源。

Xiaolong Su

A symmetric two-mode Gaussian entangled state is used to investigate the effect of excess noise on entanglement sudden death and Gaussian quantum discord with continuous variables. The results show that the excess noise in the channel can lead to entanglement sudden death of a symmetric two-mode Gaussian entangled state, while Gaussian quantum discord never vanishes. As a practical application, the security of a quantum key distribution (QKD) scheme based on a symmetric two-mode Gaussian entangled state against collective Gaussian attacks is analyzed. The calculation results show that the secret key cannot be distilled when entanglement vanishes and only quantum discord exists in such a QKD scheme.

Alexander Streltsov, Hermann Kampermann, Dagmar Bruß

L. F. M. Borelli, L. S. Aguiar, J. A. Roversi +1 more