论文标题
量子网络中的会议关键协议
Conference key agreement in a quantum network
论文作者
论文摘要
量子会议密钥协议（QCKA）允许多个用户从共享的多目标纠缠状态中建立安全密钥。在量子网络中，可以使用N Qubit Greenberger-Horne-Zeilinger（GHz）状态的单个副本有效地实施此协议，以使安全的N-用户会议密钥位散布，而最多在N-1纠缠对中则在传统的配对协议中消耗了n-1纠缠对。我们证明了GHz状态在由Photonic Six-user量子网络组成的测试台中提供的优势，其中四个用户可以使用网络路由技术蒸馏出GHz状态或QCKA所需的铃铛对数。在渐近限制中，我们在比较两个方案时报告了会议关键率的两倍以上。我们推断我们的数据集以证明GHz协议的资源优势在考虑到有限键效应时仍然存在。
Quantum conference key agreement (QCKA) allows multiple users to establish a secure key from a shared multi-partite entangled state. In a quantum network, this protocol can be efficiently implemented using a single copy of a N-qubit Greenberger-Horne-Zeilinger (GHZ) state to distil a secure N-user conference key bit, whereas up to N-1 entanglement pairs are consumed in the traditional pair-wise protocol. We demonstrate the advantage provided by GHZ states in a testbed consisting of a photonic six-user quantum network, where four users can distil either a GHZ state or the required number of Bell pairs for QCKA using network routing techniques. In the asymptotic limit, we report a more than two-fold enhancement of the conference key rate when comparing the two protocols. We extrapolate our data set to show that the resource advantage for the GHZ protocol persists when taking into account finite-key effects.
