The project is essentially divided into three parts, each of which contribute to the provision of traceability for Arden Photonics Fibre Geometry instrumentation leading to increased sales through greater market confidence in the products. 1) Investigate the existing NPL primary measuring instrument for characterizing fibre cladding mean diameter in order to extend the operating range to 400 micron cladding diameter and improve NPL's measurement service capability in response to developments within the fibre communications and photonics industry. Assess different camera performances using alterations to the optical system to determine magnification and scaling factors. Initialise the process to determine the best measurement uncertainty. 2) Build and supply a traceable calibrated 400 micron cladding diameter reference artefact within a protective retractable holder to Arden Photonics. This includes liaison with Arden regarding the cleaving process and the NPL dimensional group for traceable contact metrology. 3) Carry out measurements on the Arden FGC instrument with 400 micron cladding diameter artefacts using traceable artefacts and produce a report on the FGC performance at this range. This report will help Arden to better understand the uncertainties of its instrument at larger diameters.

IPN-Bio (Integrated Photonic-Nano Technologies for Bio-applications) aims to foster and develop long-term international, interdisciplinary and inter-sectoral collaboration between Europe, USA, Latin America and China. IPN-Bio consortium consists of 13 world-leading organisations from eight countries (4 EU universities, 3 EU companies, 6 TC Partner organisations) working at the frontier of the field with the complementary expertise in the multidiscipline of Photonics, Nanotechnology and Biotechnology. IPN-Bio will implement strategies of excellence science through a total of 218 person-month of structured international and inter-sectoral staff exchanges involving 36 individual researchers. The R&I staff exchanges and network activities will provide an excellent platform for the exchanged researchers to share the knowledge and ideas, transfer the skills and boost career opportunities. The project’s objectives and challenges present a balanced mix between industrial application focused knowledge transfer and development and more far-looking studies for potentially ground-breaking applications by exploiting new emerging opportunities with the integration of photonics technology and advanced nanomaterials for the applications in health care, biomedical diagnosis, food safety and environmental monitoring. The IPN-Bio network will forge strong collaborative relationships between participating organisations, push Europe at the forefront of global biophotonics research community, and strengthen Europe’s human capital, competitiveness and economy growth.

Over the last decade, much interest of scientists and engineers working in optics and photonics has been attracted to the research and development of miniature devices based on the phenomenon of slow light. The idea of slow light consists in reducing its average speed of propagation by forcing light to oscillate and circulate in specially engineered microscopic photonic structures (e.g., photonic crystals and coupled ring resonators). Researchers anticipated that slow light devices will have revolutionary applications in communications, optical and radio signal processing, quantum computing, sensing, and fundamental science. For this reason, the research on slow light has been conducted in many academic laboratories and industrial research centres including telecommunications giants IBM, Intel, and NTT. However, in spite of significant progress, it had been determined that current photonic fabrication technologies are unable to produce practical slow light devices due to the major barriers: the insufficient fabrication precision and substantial attenuation of light. To overcome these barriers, this project will develop a new photonic technology, Surface Nanoscale Axial Photonics (SNAP) which will allow us to demonstrate miniature photonics devices with unprecedentedly high precision and low loss. SNAP is a new microphotonics fabrication platform invented by the PI of this project. In contrast to previously considered slow light structures based on circulation of light in coupled ring resonators and oscillations photonic crystals, the SNAP platform employs whispering gallery modes of light in an optical fibre, which circulate near the fibre surface and slowly propagate along its axis. The speed of axial propagation of these modes is so slow that it can be fully controlled by dramatically small nanoscale variations of the fibre radius. This project will develop the advanced SNAP technology for fabrication of ultraprecise, ultralow loss, tuneable, switchable and fully reconfigurable miniature slow light devices establishing the groundwork for their revolutionary applications in future Information and Communication Technologies. The success of the project will place the UK in the centre of this revolutionary development.

Technologies underpin economic and industrial advances and improvements in healthcare, education and societal and public infrastructure. Technologies of the future depend on scientific breakthroughs of the past and present, including new knowledge bases, ideas, and concepts. The proposed international network of interdisciplinary centre-to-centre collaborations aims to drive scientific and technological progress by advancing and developing a new science platform for emerging technology - the optical frequency comb (OFC) with a range of practical applications of high industrial and societal importance in telecommunications, metrology, healthcare, environmental applications, bio-medicine, food industry and agri-tech and many other applications. The optical frequency comb is a breakthrough photonic technology that has already revolutionised a range of scientific and industrial fields. In the family of OFC technologies, dual-comb spectroscopy plays a unique role as the most advanced platform combining the strengths of conventional spectroscopy and laser spectroscopy. Measurement techniques relying on multi-comb, mostly dual-comb and very recently tri-combs, offer the promise of exquisite accuracy and speed. The large majority of initial laboratory results originate from cavity-based approaches either using bulky powerful Ti:Sapphire lasers, or ultra-compact micro-resonators. While these technologies have many advantages, they also feature certain drawbacks for some applications. They require complex electronic active stabilisation schemes to phase-lock the different single-combs together, and the characteristics of the multi-comb source are not tuneable since they are severely dictated by the opto-geometrical parameters of the cavity. Thus, their repetition rates cannot be optimised to the decay rates of targeted samples, nor their relative repetition rates to sample the response of the medium. Such lack of versatility leads to speed and resolution limitations. These major constraints impact the development of these promising systems and make difficult their deployment outside the labs. To drive OFC sources, and in particular, multi-comb source towards a tangible science-to-technology breakthrough, the current state of the art shows that a fundamental paradigm shift is required to achieve the needs of robustness, performance and versatility in repetition rates and/or comb optical characteristics as dictated by the diversity of applications. In this project we propose and explore new approaches to create flexible and tunable comb sources, based on original design concepts. The novelty and transformative nature of our programme is in addressing engineering challenges and designs treating nonlinearity as an inherent part of the engineering systems rather than as a foe. Using the unique opportunity provided by the EPSRC international research collaboration programme, this project will bring together a critical mass of academic and industrial partners with complimentary expertise ranging from nonlinear mathematics to industrial engineering to develop new concepts and ideas underpinning emerging and future OFC technologies. The project will enhance UK capabilities in key strategic areas including optical communications, laser technology, metrology, and sensing, including the mid-IR spectral region, highly important for healthcare and environment applications, food, agri-tech and bio-medical applications. Such a wide-ranging and transformative project requires collaborative efforts of academic and industrial groups with complimentary expertise across these fields. There are currently no other UK projects addressing similar research challenges. Therefore, we believe that this project will make an important contribution to UK standing in this field of high scientific and industrial importance.

It is recognised that global communication systems are rapidly approaching the fundamental information capacity of current transmission technologies. Saturation of the capacity of the communication systems might have detrimental impact on the economy and social progress and public, business and government activities. The aim of the proposed research is to develop, through theory and experiment, disruptive approaches to unlocking the capacity of future information systems that go beyond the limits of current optical communications systems. The research will combine techniques from information theory, coding, study of advanced modulation formats, digital signal processing and advanced photonic concepts to make possible breakthrough developments to ensure a robust communications infrastructure beyond tomorrow. Increasing the total capacity of communication systems requires a multitude of coordinated efforts: new materials and device bases, new fibres, amplifiers and network paradigms, new ways to generate, transmit, detect and process optical signals and information itself - all must be addressed. In particular, the role of fibre communications, providing the capacity for a lion share of the total information traffic, is vital. One of the important directions to avoid the so-called "capacity crunch", the exhaust in fibre capacity - is to develop completely new transmission fibres and amplifiers. However, there is also a growing need for complimentary actions - innovative and radically novel approaches to coding, transmission and processing of information. Our vision is focused on the need to quantify the fundamental limits to the nonlinear channels carried over optical fibres and to develop techniques to approach those limits so as to maximise the achievable channel capacity. The information capacity of a linear channel with white Gaussian noise is well known and is defined by the Shannon limit. Wireless systems can approach this limit very closely - to within fractions of a dB. However, the optical channel is nonlinear. Fibre nonlinearity mixes noise with signal. Therefore, results of the linear theories on capacity can be applied in fibre channels only in the limit of very small nonlinear effects. Optical communication systems are undergoing another revolution with the development of techniques of coherent detection, the ability to detect both the amplitude and the phase of a transmitted signal and use of digital signal processing techniques to reconstruct the original signal. Use of the optical phase in emerging coherent transmission schemes opens up fundamentally new theoretical and technical possibilities most as yet unexplored. The challenge is to understand to what degree optical nonlinearity can also be compensated or, indeed, used to unlock the fibre capacity, maximise both the information transmission rate and the total bandwidth, to determine the fundamental Shannon limit for nonlinear channels and to develop methods to approach this capacity. We propose to explore fundamentally new nonlinear information technologies and to develop a practical design framework based on integration of DSP techniques, novel modulation formats, and novel source and line coding approaches tailored to the nonlinear optical channels. We believe this to be the key to designing the intelligent information infrastructure of the future.