A quantum router architecture for high-fidelity entanglement flows in quantum networks
A quantum router architecture for high-fidelity entanglement flows in quantum networks
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DOI：
10.1038/s41534-022-00582-8
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发表时间：
2022-06-29
影响因子：
7.6
通讯作者：
Englund, Dirk
中科院分区：
文献类型：
--
作者：
Lee, Yuan;Bersin, Eric;Englund, Dirk
在过去的十年里，在实验上实现量子中继器的组成部分取得了巨大的进展。采用多路复用量子存储器的中继器架构已被提出用于提高纠缠分布率，但一个公开的挑战是在长距离链路上保持纠缠保真度。在这里，我们通过一个量子路由器架构来解决这个问题，该架构包括许多量子存储器，这些存储器连接在一个光子交换机中，以代理量子网络上的纠缠流。我们使用基于事件的模拟器计算了该架构下的纠缠分布速率和保真度，发现随着复用深度的增加，路由器在不显著降低纠缠分布速率的情况下提高了纠缠保真度。具体来说，路由器允许信道无损不变保真度，即与无损链路实现的保真度相同。此外，该方案在不需要全局网络信息的情况下，自动对整个网络中的纠缠流进行优先级排序。所提出的架构使用当今的光子技术，为近期可部署的多节点量子网络开辟了一条道路。
The past decade has seen tremendous progress in experimentally realizing the building blocks of quantum repeaters. Repeater architectures with multiplexed quantum memories have been proposed to increase entanglement distribution rates, but an open challenge is to maintain entanglement fidelity over long-distance links. Here, we address this with a quantum router architecture comprising many quantum memories connected in a photonic switchboard to broker entanglement flows across quantum networks. We compute the rate and fidelity of entanglement distribution under this architecture using an event-based simulator, finding that the router improves the entanglement fidelity as multiplexing depth increases without a significant drop in the entanglement distribution rate. Specifically, the router permits channel-loss-invariant fidelity, i.e. the same fidelity achievable with lossless links. Furthermore, this scheme automatically prioritizes entanglement flows across the full network without requiring global network information. The proposed architecture uses present-day photonic technology, opening a path to near-term deployable multi-node quantum networks.