Quantum technologies promise a transformation of measurement, communication and computation by using ideas originating from quantum physics. The UK was the birthplace of many of the seminal ideas and techniques; the technologies are now ready to translate from the laboratory into industrial applications. Since international companies are already moving in this area, there is a critical need across the UK for highly-skilled researchers who will be the future leaders in quantum technology. Our proposal is driven by the need to train this new generation of leaders. They will need to be equipped to function in a complex research and engineering landscape where quantum physics meets cryptography, complexity and information theory, devices, materials, software and hardware engineering. We propose to train a cohort of leaders to meet these challenges within the highly interdisciplinary research environment provided by UCL, its commercial and governmental laboratory partners. In their first year the students will obtain a background in devices, information and computational sciences through three concentrated modules organized around current research issues. They will complete a team project and a longer individual research project, preparing them for their choice of main research doctoral topic at the end of the year. Cross-cohort training in communication skills, technology transfer, enterprise, teamwork and career planning will continue throughout the four years. Peer to peer learning will be continually facilitated not only by organized cross-cohort activities, but also by the day to day social interaction among the members of the cohort thanks to their co-location at UCL.

The description of the laws of quantum mechanics saw a transformation in society's understanding of the physical world-for the first time we understood the rules that govern the counterintuitive domain of the very small. Rather than being just passive observers now scientists are using these laws to their advantage and quantum phenomena are providing us with methods of improved measurement and communication; furthermore they promise a revolution in the way materials are simulated and computations are performed. Over the last decade significant progress has been made in the application of quantum phenomena to meeting these challenges. This "Engineering Photonic Quantum Technologies" Programme Grant goes significantly beyond previous achievements in the quantum technology field. Through a series of carefully orchestrated work packages that develop the underlying materials, systems engineering, and theory we will develop the knowledge and skills that enable us to create application demonstrators with significant academic and societal benefit. For the first time in quantum technologies we are combining materials and device development and experimental work with the important theoretical considerations of architectures and fault tolerant approaches. Our team of investigators and partners have the requisite expertise in materials, individual components, their integration, and the underpinning theory that dictates the optimal path to achieving the programme goals in the presence of real-world constraints. Through this programme we will adopt the materials systems most capable of providing application specific solutions in each of four technology demonstrations focused on quantum communications, quantum enhanced sensing, the construction of a multiplexed single-photon source and information processing systems that outperform modern classical analogues. To achieve this, our underlying technology packages will demonstrate very low optical-loss waveguides which will be used to create the necessary 'toolbox' of photonic components such as splitters, delays, filters and switches. We will integrate these devices with superconducting and semiconducting single-photon detector systems and heralded single-photon sources to create an integrated source+circuit+detector capability that becomes the basis for our technology demonstrations. We address the challenge of integrating these optical elements (in the necessary low-temperature environment) with the very low latency classical electronic control systems that are required of detection-and-feedforward schemes such as multiplexed photon-sources and cluster-state generation and computation. At all times a thorough analysis of the performance of all these elements informs our work on error modelling and fault tolerant designs; these then inform all aspects of the technology demonstrators from inception, through decisions on the optimal materials choices for a system, to the layout of a circuit on a wafer. With these capabilities we will usher in a disruptive transformation in ICT. We will demonstrate mutli-node quantum key distribution (QKD) networks, high-bit rate QKD systems with repeaters capable of spanning unlimited distances. Our quantum enhanced sensing will surpass the classical shot noise limit and see the demonstration of portable quantum-enhanced spectroscopy system. And our quantum information processors will operate with 10-qubits in a fault tolerant scheme which will provide the roadmap to 1,000 qubit cluster state computing architectures.

We aim to grow the world's leading centre for training in quantum engineering for the emerging quantum technology (QT) industry. We have designed this CDT in collaboration with a large number of academic and industry experts, and included as partners those who will add substantially to the training and cohort experience. Through this process a consistent picture of what industry wants in future quantum engineers emerged: people who can tackle the hardest intellectual challenges, recognising the end goal of their research, with an ability to move from fundamental physics towards the challenges of engineering and miniaturising practical systems, who understands the capabilities of other people (and why they are useful). Industry wants people with good decision-making, communication and management skills, with the ability to work across discipline boundaries (to a deadline and a budget!) and build interdisciplinary teams, with the ability to translate a problem from one domain to another. Relevant work experience, knowledge of entrepreneurship, industrial R&D operations and business practices are essential. By forming a hub of unrivalled international excellence in quantum information and photonics, surrounded by world-class expertise in all areas of underpinning science and technology and the scientific and technological application areas of QT, and a breadth of academic and industry partners, we will deliver a new type of training: quantum engineering. Bristol has exceptional international activity in the areas that surround the hub: from microelectronics and high performance computing to system engineering and quantum chemistry. The programme will be delivered in an innovative way-focussing particularly on cohort learning-and assessed by a variety of different means, some already in existence in Bristol. We believe that we are attempting something new and exciting that has the potential to attract and train the best students to ensure that the resulting capacity is world-class, thus providing real benefits to the UK economy.

The EPSRC Quantum Computing and Simulation Hub will enable the UK to be internationally leading in Quantum Computing and Simulation. It will drive progress toward practical quantum computers and usher in the era where they will have revolutionary impact on real-world challenges in a range of multidisciplinary themes including discovery of novel drugs and new materials, through to quantum-enhanced machine learning, information security and even carbon reduction through optimised resource usage. The Hub will bring together leading quantum research teams across 17 universities, into a collaboration with more than 25 national and international commercial, governmental and academic entities. It will address critical research challenges, and work with partners to accelerate the development of quantum computing in the UK. It will foster a generation of UK-based scientists and engineers equipped with the new skill sets needed to make the UK into a global centre for innovation as the quantum sector emerges. The Hub will engage with government and citizens so that there is a wide appreciation of the potential of this transformative technology, and a broad understanding of the issues in its adoption. Hub research will focus on the hardware and software that will be needed for future quantum computers and simulators. In hardware we will advance a range of different platforms, encompassing simulation, near term quantum computers, and longer term fully scalable machines. In software the Hub will develop fundamental techniques, algorithms, new applications and means to verify the correct operation of any future machine. Hardware and software research will be closely integrated in order to provide a full-stack capability for future machines, enabled by the broad expertise of our partners. We will also study the architecture of these machines, and develop emulation techniques to accelerate their development. Success will require close engagement with a wide range of commercial and government organisations. Our initial partners include finance (OSI), suppliers (Gooch & Housego, Oxford Instruments, E6), integrators and developers (OQC, QM, CQC, QxBranch, D-Wave), users from industry (Rolls-Royce, Johnson Matthey, GSK, BT, BP, TrakM8, Airbus, QinetiQ) and government (DSTL, NCSC), and other research institutions (NPL, ATI, Heilbronn, Fraunhofer). We will build on this strong network using Industry Days, Hackathons and targeted workshops, authoritative reports, and collaborative projects funded through the Hub and partners. Communications and engagement with the community through a range of outreach events across the partnership will inform wider society of the potential for quantum computing, and we will interact with policy makers within government to ensure that the potential benefits to the UK can be realised. The Hub will train researchers and PhD students in a wide range of skills, including entrepreneurship, intellectual property and commercialisation. This will help deliver the skilled workforce that will be required for the emerging quantum economy. We will work with our partners to deliver specific training for industry, targeting technical, commercial and executive audiences, to ensure the results of the Hub and their commercial and scientific opportunities are understood. The Hub will deliver demonstrations, new algorithms and techniques, spinout technologies, and contribute to a skilled workforce. It will also engage with potential users, the forthcoming National Centre for Quantum Computing, the global QC community, policy makers and the wider public to ensure the UK is a leader in this transformative new capability.