Institute for Theoretical Physics, ETH Zurich, 8093 Zurich, Switzerland.
Nat Commun. 2012 Jan 17;3:634. doi: 10.1038/ncomms1631.
Despite enormous theoretical and experimental progress in quantum cryptography, the security of most current implementations of quantum key distribution is still not rigorously established. One significant problem is that the security of the final key strongly depends on the number, M, of signals exchanged between the legitimate parties. Yet, existing security proofs are often only valid asymptotically, for unrealistically large values of M. Another challenge is that most security proofs are very sensitive to small differences between the physical devices used by the protocol and the theoretical model used to describe them. Here we show that these gaps between theory and experiment can be simultaneously overcome by using a recently developed proof technique based on the uncertainty relation for smooth entropies.
尽管量子密码学在理论和实验方面取得了巨大进展，但大多数当前实现的量子密钥分发的安全性仍未得到严格确立。一个重要问题是，最终密钥的安全性强烈依赖于合法方之间交换的信号数量 M。然而，现有的安全性证明通常仅在 M 取非常大的不切实际的值时才渐近有效。另一个挑战是，大多数安全性证明对协议中使用的物理设备与用于描述它们的理论模型之间的微小差异非常敏感。在这里，我们表明可以通过使用最近基于平滑熵不确定性关系开发的证明技术同时克服这些理论与实验之间的差距。
