论文标题
通过数字信号处理的连续变量量子密钥分布的有限尺寸安全性
Finite-size security of continuous-variable quantum key distribution with digital signal processing
论文作者
论文摘要
与常规离散变量（DV）量子密钥分布（QKD）相比，具有同源性/异差测量的连续变量（CV）QKD具有较低成本实施和与波长的相关性的不同优势。另一方面，其连续的性质使得很难适应实用的信号处理，这始终是离散的，导致到目前为止缺乏完整的安全证明。在这里，我们提出了一种紧密而强大的方法，可以通过杂作测量来估计光脉冲对连贯状态的保真度。然后，我们根据DV QKD的证明技术来构建一个二进制调制的CV QKD协议，并在针对一般连贯攻击的有限键尺寸制度中证明其安全性。这样的完整的安全性证明在利用简历QKD的好处方面取得了重要的里程碑。
In comparison to conventional discrete-variable (DV) quantum key distribution (QKD), continuous-variable (CV) QKD with homodyne/heterodyne measurements has distinct advantages of lower-cost implementation and affinity to wavelength division multiplexing. On the other hand, its continuous nature makes it harder to accommodate to practical signal processing, which is always discretized, leading to lack of complete security proofs so far. Here we propose a tight and robust method of estimating fidelity of an optical pulse to a coherent state via heterodyne measurements. We then construct a binary phase modulated CV QKD protocol and prove its security in the finite-key-size regime against general coherent attacks, based on proof techniques of DV QKD. Such a complete security proof achieves a significant milestone in exploiting the benefits of CV QKD.
