Next-Generation QKD Systems

Expected Outcome: This action will strengthen Europe's strategic autonomy in quantum-secure communications by advancing core QKD technologies and integration capabilities. Expected results include: Development and demonstration of next-generation QKD systems, with a focus on cost-effectiveness and integration, with specific measurable improvements in one of the following parameters or features: (i) key rate (>1 Mbps over metropolitan distances), (ii) operational coverage of a network at the regional scale, >300 km for fibre-based QKD, including e.g. twin field and free-space links also for non-wired segments and for redundancy, (iii) development and demonstration of advanced quantum cryptographic protocols beyond QKD with provable security advantage over classical cryptographic systems. Implementation of hybrid quantum-classical cryptographic frameworks combining QKD and post-quantum cryptography (PQC), tested on clearly defined real-world applications. Integration of quantum communication components with network equipment and orchestration systems (e.g., software-defined networking). Validation of QKD-based security in high-priority use cases beyond EuroQCI infrastructure, including: Critical infrastructure monitoring (e.g., energy grid telemetry), Long-term secure cloud storage, Industrial control systems (e.g., transport, manufacturing), Secure multi-site enterprise communications. Strengthened European supply chain through the development of certifiable, standardised, and scalable QKD components. This action must address at least two core technical roadblocks defined in the SRIA 2030 for quantum-secure communication. These include scalability challenges in next-generation QKD protocols (e.g. MDI-QKD, DI-QKD) and the integration of QKD with PQC. Proposals are also encouraged to target at least one functionality beyond QKD in prepare-and-measure and one in entanglement-based scenarios, as identified for future quantum networks in the SRIA 2030. Scope: The action should support applied R&D in advanced QKD systems and their integration into future secure communication networks, avoiding overlap with EuroQCI deployment efforts. Proposals must include: Development and experimental validation of advanced QKD protocols and systems such as: Continuons-variable QKD (CV-QKD), Measurement-device-independent or device-independent QKD, Twin-field QKD (TF-QKD), Design and implementation of QKD integration into classical and optical networking infrastructure: Compatibility with existing network equipment (e.g., routers, switches), Interface development for SDN…