可扩展量子网络研究取得重大突破 我国科学家在国际上首次构建出可扩展量子中继的基本模块

Core Insights - The research team from the University of Science and Technology of China has achieved a significant breakthrough in scalable quantum network research by constructing the basic module of a scalable quantum relay, making long-distance quantum networks a realistic possibility [1][2] - They have successfully established long-lived quantum entanglement between single atomic nodes over long distances and have, for the first time, surpassed the 100-kilometer transmission distance for device-independent quantum key distribution, improving upon previous international experimental levels by more than two orders of magnitude [2] Group 1 - The ultimate goal of quantum information science is to build efficient and secure quantum networks, with the fundamental element being the distribution of long-distance deterministic quantum entanglement [1] - The inherent loss in optical fibers leads to an exponential decay in the efficiency of quantum entanglement transmission with distance, posing the greatest challenge in constructing scalable quantum networks [1] - The quantum relay scheme is an effective solution to address the transmission loss in optical fibers, potentially enhancing the efficiency of entanglement distribution over 1000 kilometers by 100 billion billion times compared to direct transmission [1] Group 2 - The research team developed long-lived trapped ion quantum memory, high-efficiency ion-photon communication interfaces, and high-fidelity single-photon entanglement protocols to achieve long-lived quantum entanglement, significantly exceeding the time required to establish entanglement [2] - The successful construction of the basic module for scalable quantum relays marks a transition from theoretical concepts to realistic possibilities for fiber-based quantum networks [3]