This action will advance Europe’s leadership in trapped-ion quantum computing by achieving the following key outcomes:

• Establishment of a full-stack ion-trap quantum computer aiming at more than 1.000 qubits, fully integrated into high-performance computing (HPC) systems, and accessible via the cloud.
• Demonstration of quantum advantage for selected real-world applications, validated against benchmarks.
• Strengthened European capabilities to develop modular, interoperable, and scalable quantum computing architectures.
• Implementation and demonstration of advanced error correction and fault-tolerant quantum computing techniques.
• Integration of full-stack hardware-software systems with standardised and certified interfaces.
• Engagement with industry and academia through open access to quantum computing resources and co-design of applications.

The action should support the scale-up of European trapped-ion quantum computing platforms, aiming at technological maturity and usability for industrial and scientific applications. In particular, the action must address at least two major technical roadblocks defined in the Strategic Research and Industry Agenda (SRIA 2030) for trapped-ion quantum computing. These include the limited scalability of ion trap architectures, particularly the need for modular designs and inter-chain coupling, and the integration of photonic components for laser delivery, enabling compact and fault-tolerant systems. The proposal is expected to demonstrate system-level innovation and practical application addressing these and other equally critical challenges.

The proposal should also:

• Develop a full-stack trapped-ion quantum computer with more than 1000 physical qubits, including:
  • Initialisation, manipulation, and readout fully integrated into the cryogenic setup.
  • Reduced system footprint via standardised interfaces and integrated waveguides.
• Advance scalable error correction and fault-tolerant computing:
  • Develop and benchmark error correction codes suitable for trapped-ion architectures.
  • Demonstrate error mitigation in noisy environments and real-life quantum information tasks.
• Enable real-life application testing:
  • Select and implement at least two practical use cases (aligned with industrial or scientific challenges).
  • Demonstrate computational advantage over classical simulations where possible or show progress towards it.
• Develop standards and modular interoperability:
  • Establish interface specifications for both hardware and software layers, enabling integration across vendors and platforms.
  • Align with European efforts on standardisation, benchmarking, and certification.
• Integrate with classical computing infrastructures:
  • Ensure seamless operation alongside HPC resources, with remote access and hybrid quantum-classical workflows.
• Provide access and foster ecosystem participation:
  • Support researchers and industry (including SMEs) with open, cloud-based access, comprehensive user documentation, and training resources.
• Contribute to a sustainable European supply chain:
  • Address key technological components such as lasers, ion traps, control electronics, and packaging solutions, aiming for independent and robust sourcing