Center for Quantum Information and Quantum Control, Department of Electrical & Computer Engineering, University of Toronto, Toronto, Ontario, M5S 3G4, Canada.
Phys Rev Lett. 2012 Mar 30;108(13):130503. doi: 10.1103/PhysRevLett.108.130503.
How to remove detector side channel attacks has been a notoriously hard problem in quantum cryptography. Here, we propose a simple solution to this problem--measurement-device-independent quantum key distribution (QKD). It not only removes all detector side channels, but also doubles the secure distance with conventional lasers. Our proposal can be implemented with standard optical components with low detection efficiency and highly lossy channels. In contrast to the previous solution of full device independent QKD, the realization of our idea does not require detectors of near unity detection efficiency in combination with a qubit amplifier (based on teleportation) or a quantum nondemolition measurement of the number of photons in a pulse. Furthermore, its key generation rate is many orders of magnitude higher than that based on full device independent QKD. The results show that long-distance quantum cryptography over say 200 km will remain secure even with seriously flawed detectors.
如何消除探测器侧信道攻击一直是量子密码学中一个众所周知的难题。在这里，我们提出了一种简单的解决方案——测量设备无关量子密钥分发（QKD）。它不仅消除了所有的探测器侧信道，而且还将与传统激光器的安全距离提高了一倍。我们的方案可以用低探测效率和高度损耗的信道的标准光学元件来实现。与之前的全设备无关 QKD 的解决方案相比，我们的想法的实现不需要探测器具有接近 1 的探测效率，并且不需要量子比特放大器（基于量子隐形传态）或脉冲中光子数的量子非破坏测量。此外，它的密钥生成率比基于全设备无关 QKD 的密钥生成率高出几个数量级。结果表明，即使探测器存在严重缺陷，长达 200 公里以上的远距离量子密码学仍将保持安全。
