crossroads magazine Quantum technologies are advancing across three fields: computing, communication and sensing. Luxembourg is determined to harness the potential of quantum technologies to drive scientific, techno- logical and economic progress. The objectives of the national quantum strategy are to develop expertise and services in quantum computing, establish secure quantum communica- tions and generate economic value from quantum technologies. The strategy builds on Luxembourg’s strengths in finance, space, cybersecurity and high-performance computing. It connects these capabilities with public research, industrial projects and international part- nerships to develop practical applications and services. In quantum computing, potential applications include financial modelling, portfolio optimisation, risk analysis, drug discovery and logistics optimisa- tion. In quantum communication, banks, insurance companies and government institutions are likely early adopters, driven by security requirements and growing regulatory pressure. For quantum sensing, POST Luxembourg has already deployed a commer- cial optical atomic clock in its network core, protect- ing timing systems against jamming and spoofing. A platform for hybrid computing Luxembourg’s most concrete quantum infrastructure project is MeluXina-Q, a EuroHPC-hosted quantum computer that will be integrated into the nation- al high-performance computing facility at a Tier IV-certified data centre. This results in an environ- ment where classical, AI and quantum computing re- sources can be combined. This hybrid model gives researchers and companies a practical way to explore quantum applications while continuing to use established computing systems. “MeluXina-Q will be a real game-changer for this type of research. It will also help companies assess potential applications and develop the capabilities needed to use the technology,” said Marko Rančić, As- sociate Professor in High Performance and Quantum Computing at the University of Luxembourg. He stud- ies applied quantum computing alongside high-per- formance computing. One of his most prominent collaborations, EMQUANT-PT, examined quantum phase transitions with the Korea Advanced Institute of Science and Technology. From fibre to orbit Luxembourg was among the first seven EU Member States to sign the European Quantum Communica- tion Infrastructure declaration in 2019. Since then, the country has developed an experimental testbed for quantum key distribution (QKD) – a secure method for sharing secret encryption keys between two parties us- ing the rules of quantum physics – at the University of Luxembourg and completed a terrestrial cross-border connection with Belgium. Further projects are explor- ing integrated networks that combine fibre-optic and satellite links. One of them, EAGLE-1, adds a space-based dimen- sion. Led by satellite operator SES and developed with 20 European partners, the project is an in-orbit demonstrator for QKD between satellites and ground networks. It aims to enable secure data transmission across Europe and beyond, supporting sectors that handle critical and sensitive data. © Google DeepMind