论文标题
具有离散相随机化的量子键分布的有限键分析
Finite-key analysis for quantum key distribution with discrete phase randomization
论文作者
论文摘要
量子密钥分布（QKD）允许两个远程各方共享信息理论的秘密密钥。许多QKD协议假设编码状态的阶段可以从0到2 PI连续进行随机分配，但是在实验中可能值得怀疑。在最近提出的双场（TF）QKD中，这种情况尤其如此，该QKD受到了很多关注，因为它可以大大提高关键率，甚至超过一些理论上的损失限制。作为一个直观的解决方案，可以引入离散的相对性化而不是连续的相关化。但是，在有限键区域中具有离散阶段随机化的QKD协议的安全性证明仍然缺失。在这里，我们开发了一种基于共轭测量和量子状态区分的技术，在这种情况下，安全性。我们的结果表明，具有合理数量离散随机阶段的TF-QKD，例如{0，pi/4，pi/2，...，7pi/4}的8个阶段可以实现令人满意的性能。更重要的是，作为有限键区域中具有离散相位随机化的TF-QKD的第一个证明，我们的方法也适用于其他QKD协议。
Quantum key distribution(QKD) allows two remote parties to share information-theoretic secret keys. Many QKD protocols assume the phase of encoding state can be continuous randomized from 0 to 2 pi, which, however, may be questionable in experiment. This is particularly the case in the recently proposed twin-field(TF) QKD, which has received a lot of attention, since it can increase key rate significantly and even beat some theoretical rate-loss limits. As an intuitive solution, one may introduce discrete phase-randomization instead of continuous one. However, a security proof for a QKD protocol with discrete phase-randomization in finite-key region is still missing. Here we develop a technique based on conjugate measurement and quantum state distinguishment to ana-lyze the security in this case. Our result shows that TF-QKD with reasonable number of discrete random phases, e.g. 8 phases from {0, pi/4, pi/2, ..., 7pi/4}, can achieve satisfactory performance. More importantly, as a the first proof for TF-QKD with discrete phase-randomization in finite-key region, our method is also applicable in other QKD protocols.
