Field Demonstration of Trusted-Node QKD over Deployed Single-Mode and Multi-Core Fiber Infrastructure
quantumcomputingreport.com Jun 9, 2026

Field Demonstration of Trusted-Node QKD over Deployed Single-Mode and Multi-Core Fiber Infrastructure

AI-summarised brief · reviewed before publication

A collaborative research team has successfully demonstrated a long-haul, trusted-node Quantum Key Distribution (QKD) link over 303 km in southeastern Sweden. The link combines standard single-mode fiber with a multi-core fiber access segment, integrating into a dynamically reconfigurable telecommunications network. The team modified commercial systems to interface with external detectors, yielding an upgrade in the Secret Key Rate. The system maintained positive key rates while dynamically switching the QKD channel and coexisted with a classical 10 Gbps Ethernet data channel. The demonstration operated continuously over 92 hours, feeding raw key blocks into integrated Key Management Systems.