我国科学家在可扩展量子网络研究方面取得重大突破

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-atom nodes over long distances and have, for the first time, surpassed the 100-kilometer transmission distance for device-independent quantum key distribution [1][2] Group 1 - The ultimate goal of quantum information science is to build efficient and secure quantum networks, with long-distance deterministic quantum entanglement distribution being a fundamental element [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, enabling entanglement distribution over distances of 1,000 kilometers, which could enhance efficiency 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, achieving long-lived quantum entanglement that significantly exceeds the time required to establish entanglement [2] - The successful construction of the basic module for scalable quantum relays makes long-distance quantum networks feasible [2] - The breakthrough signifies that fiber-based quantum networks utilizing quantum entanglement are transitioning from theoretical concepts to practical possibilities [2]