Year: 2025
Type: article
Abstract: Quantum entanglement networks have garnered significant attention due to the inherent security provided by quantum physics. The networks aim to connect a multitude of users with a high secure key rate (SKR). Fully connected networks have been demonstrated using wavelength-division multiplexing architectures. However, the SKR of such networks remains challenging due to the limited brightness of quantum photon-pair sources and the loss introduced by cascaded filtering components. We present high-rate quantum entanglement networks that leverage a broadband quantum light source with high brightness and an industry-grade flexible wavelength-selective switching technique with uniform loss. By implementing the BBM92 protocol, we achieve an SKR of 28.19 kbps in a four-user network, representing a two-order-of-magnitude improvement over previous implementations. After transmission through a 40-km fiber spool, the SKR remains as high as 3.58 kbps and stays positive over distances up to 250 km. Furthermore, the flexibility of our scheme is illustrated by constructing a six-user network, achieving SKRs of 4.21 kbps and 0.45 kbps without and with a 40-km fiber spool, respectively. These results demonstrate a practical approach to enhancing the SKR and scalability in entanglement-based quantum networks, offering a feasible solution for deploying metropolitan and backbone quantum communication systems.
Source: Advanced Photonics
Institutions: University of Electronic Science and Technology of China, PLA Academy of Military Science, National University of Defense Technology, Chinese Academy of Sciences, Shanghai Institute of Microsystem and Information Technology, University of Science and Technology of China, CAS Key Laboratory of Quantum Information, USTC
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W4414554162