Over the next few decades, quantum computing (QC) will transform the way we design new materials, plan complex logistics and solve a wide range of problems that conventional computers cannot address. The Hub for Quantum Computing via Integrated and Interconnected Implementations (QCI3) brings together >50 investigators across 20 universities to address key challenges, and deliver applications across diverse areas of engineering and science. We will work with 27 industrial partners, the National Quantum Computing Centre, the National Physical Laboratory, academia, regulators, Government and the wider community to achieve our goals. The Hub will focus on where collaborative academic research can make transformative progress across three interconnected themes: (T1) developing integrated quantum computers, (T2) connecting quantum computers, and (T3) developing applications for them. Objectives for each are outlined below. (T1) Developing integrated quantum computing systems, with a goal of creating quantum processors that will show real utility for specific problem examples. Objectives: OB1.1: Demonstrate quantum advantage in analogue platforms with neutral atoms and photons OB1.2: Make neutral atom quantum simulation platforms available in the cloud OB1.3: Develop new applications for these and other near-term systems (T2) A key challenge of building the million qubit machines of the future is that of 'wiring' together the quantum processors that will create such a machine. The Hub will develop technologies that help achieve this and develop models to understand how such machines will scale. Objectives : OB2.1: Develop interconnect technologies for quantum processors OB2.2: Demonstrate blind computing and multi-component networks with trapped ion quantum computers OB2.3: Demonstrate transduction and networking of superconducting processors (T3) Developing applications in science and engineering, including materials design, chemistry and fluid dynamics. Objectives: OB3.1: Develop new methods for materials and chemical system modelling and design, fluid dynamics, and quantum machine learning OB3.2: Identify the nearest routes to quantum advantage for these application areas OB3.3: Develop implementations of these algorithms on T1 and T2 Hardware These will be supported by work in overarching tools (T4) that can be used across the themes of the Hub, including error correction, digital twins, verification and software stack optimisation. Skills and training Hub partners will work with end-users, our students and researchers, and partners across the UK National Quantum Technologies Programme (UKNQTP) to ensure members of the Hub have the skills they need. Specific objectives include: Provide training in innovation, commercialisation and IP, Equality, Diversity and Inclusion and Responsible Research and Innovation (RRI) to Hub partners Provide reports and training to end-users, working in partnership with the NQCC and others Continue to provide advocacy and advice to policy makers, through work in such areas as RRI Exploitation and Engagement: The Hub will build on the strong engagement activities of the UK programme, further developing the technology pipeline. We will play a key role in strengthening and expanding the UK ecosystem through events, networking and education. Specific goals are to: Broaden the partnership of the Hub, bringing new academic, government and industrial partners into the Hub network Contribute to regulation and governance through programmes of work in standards and RRI, and close collaboration with UKNQTP partners Support the generation and protection of intellectual property within the Hub, and its exploitation Develop Hub and cross-Hub outreach initiatives, working with the RRI team, to help ensure the potential of quantum computing for societal benefit can be realised

o achieve this vision, we will address major global research challenges towards the establishment of the "quantum internet" —?globally interlinked quantum networks which connect quantum nodes via quantum channels co-existing with classical telecom networks. These research challenges include: low-noise quantum memories with long storage time; connecting quantum processors at all distance scales; long-haul and high-rate quantum communication links; large-scale entanglement networks with agile routing capabilities compatible with - and embedded in - classical telecommunicatons networks; cost-effective scalability, standardisation, verification and certification. By delivering technologies and techniques to our industrial innovation partners, the IQN Hub will enable UK academia, national laboratories, industry, and end-users to be at the forefront of the quantum networking revolution. The Hub will utilise experience in the use of photonic entanglement for quantum key distribution (QKD) alongside state-of-the art quantum memory research from existing EPSRC Quantum Technology Hubs and other projects to form a formidable consortium tackling the identified challenges. We will research critical component technology, which will underpin the future national supply chain, and we will make steps towards global QKD and the intercontinental distribution of entanglement via satellites. This will utilise the Hub Network's in-orbit demonstrator due to be launched in late 2024, as well as collaboration with upcoming international missions. With the National Quantum Computing Centre (NQCC), we will explore applications towards quantum advantage demonstrations such as secure access to the quantum cloud, achievable only through entanglement networks. Hub partner National Physical Laboratory (NPL) working with our academic partners and the National Cyber Security Centre (NCSC) will ensure that our efforts are compatible with emerging quantum regulatory standards and post-quantum cybersecurity to bolster national security. We will foster synergies with competing international efforts through healthy exchange with our global partners. The Hub's strong industrial partner base will facilitate knowledge exchange and new venture creation. Achieving the IQN Hub's vision will provide a secure distributed and entanglement-enabled quantum communication infrastructure for UK end-users. Industry, government stakeholders and the public will be able to secure data in transit, in storage and in computation, exploiting unique quantum resources and functionalities. We will use a hybrid approach with existing classical cyber-security standards, including novel emerging post-quantum algorithms as well as hardware security modules. We will showcase our ambition with target use-cases that have emerged as barriers for industry, after years of investigation within the current EPSRC QT Hubs as well as other international efforts. These barriers include security and integrity of: (1) device authentication, identification, attestation, verification; (2) distributed and cloud computing; (3) detection, measurement, sensing, synchronisation. We will demonstrate novel applications as well as identify novel figures of merit (such as resilience, accuracy, sustainability, communication complexity, cost, integrity, etc.) beyond security enhancement alone to ensure the national quantum entanglement network can be fully exploited by our stakeholders and our technology can be rapidly translated into a commercial setting.