Silicon Quantum Photonics

Quantum information science and technologies offer a completely new and powerful approach to processing and transmitting information by combining two of the great scientific discoveries of the 20th century - quantum mechanics and information theory. By encoding information in quantum systems, quantum information processing promises huge computation power, while quantum communications is already in its first stages of commercialisation, and offers the ultimate in information security. However, for quantum technologies to have as big an impact on science, technology and society as anticipated, a practical scalable integration platform is required where all the key components can be integrated to a single micro-chip technology, very much akin to the development of the first microelectronic integrated circuits.

Of the various approaches to realising quantum technologies, single particles of light (photons) are particularly appealing due to their low-noise properties and ease of manipulation at the single qubit level. It is possible to harness the quantum mechanical properties of single photons, taking advantage of strange quantum properties such as superposition and entanglement to provide new ways to encode, process and transmit information. Quantum photonics promises to be a truly disruptive technology in information processing, communications and sensing, and for deepening our understanding of fundamental quantum physics and quantum information science. However, current approaches are limited to simple optical circuits with low photon numbers, inefficient detectors and no clear routes to scalability.

For quantum optic information science to go beyond current limitations, and for quantum applications to have a significant real-world impact, there is a clear and urgent need to develop a fully integrated quantum photonic technology platform to realise large and complex quantum circuits capable of generating, manipulating and detecting large photon-number states. This Fellowship will enable the PI and his research team to develop such a technology platform, based on silicon photonics. Drawing from the advanced fabrication technologies developed for the silicon microelectronics industry, state of the art silicon quantum photonic devices will enable compact, large-scale and complex quantum circuits, experiments and applications. This technology platform will overcome the current 8-photon barrier in a scalable way, enable circuits of unprecedented complexity, and will be used to address important fundamental questions, develop new approaches to quantum communications, enhance the performance of quantum sensing, provide a platform for new routes to quantum simulations, and achieve computational complexities that can challenge the limits of conventional computing. This multidisciplinary research programme will bring together engineers, physicists and industrial partners to tackle these scientific and technological challenges.

Quantum Information Technologies (QIT), such as the silicon quantum integrated circuits to be developed in this research programme, offer a completely new paradigm to information processing and communication, and are a potential disruptive technology for Information and Communications Technologies (ICT). This research programme encompasses the critical steps required to make practical quantum devices that can not only outperform their classical counterparts (for specific operation), but also bring quantum technologies out of the research laboratory and into an industrial environment where practical breakthrough technologies can be realised for real-world applications.

The number of potential beneficiaries of this research is large, and the potential impact is far reaching, both in the mid and the longer term. Realisation of a technology that can harness the unique properties of quantum mechanics to process and transmit information whilst at the same time allowing large-scale integration and compatibility with microelectronics, could form the basis of a whole new technology sector that could have a significant impact on our society, culture and economy. There are a number of industrial partners supporting this Fellowship, and their interest and commitment is a clear indication of the anticipated impact that this potential disruptive technology could offer.

In the short term, the specific goals of this Fellowship will be of interest to specialist groups such as scientists, industrialists and the scientifically curious public, but as the technology matures the potential impact will include many areas including science, industry, healthcare, society, and the UK and global economy. Potential beneficiaries include companies that are currently commercialising secure quantum communications equipment, and their prospective customers - multinational corporations, financial institutes, large government organisations and defence. Specialist scientific communities and the general public would also gain from the development of this cutting edge research topic, and will be informed through dissemination of information in journals, conference and popular science media.

In the long term, it is difficult to predict who will be the biggest beneficiaries of this technology, but successful QITs could feed into all areas of society, just as conventional ICT and electronic devices have penetrated all areas of today's society. The technology platform developed in this Fellowship will be used to realise a handful of specific device applications and prototypes that are of direct interest and relevance to the industrial programme partners, academic collaborators, the public and the scientific community. These proof-of-principle demonstrators will form the basis of key future quantum technologies. Examples of anticipated beneficiaries and the related potential impact are:

- The scientific community: QITs would enable the investigation of new physics, biology and chemistry through the simulation of complex quantum systems;

- Industry: quantum enhanced technologies could give rise to innovations that could aid in the design and manufacture of new products, but also the improvement of existing products, such as secure communications and low energy interconnects;

- The service industry: this sector could benefit from new developments in security and new ways to process and search large amounts of information;

- Healthcare: QITs could aid in the development of new drugs, sensing and analysis equipment;

- The UK economy: QITs will generate jobs and industries that will support the growth and competitiveness of the UK.