Deployed trusted-node quantum key distribution over 300 km with a multi-core fiber access link
Researchers have successfully demonstrated a quantum key distribution (QKD) system spanning over 300 kilometers, integrating commercial QKD devices with advanced superconducting nanowire single-photon detectors. This system was tested over a deployed fiber network, including a segment of multi-core fiber designed to simulate metropolitan access links, while co-existing with classical network traffic. The experiment highlights the practical challenges and potential applications of QKD in future hybrid quantum-classical communication networks, particularly concerning throughput variations and their impact on encrypted data transmission. AI