The remarkable success of the internet is unquestioned, touching all aspects of our daily lives and commerce. This success is fundamentally underpinned by the tremendous capacity of unseen underground and undersea optical fibre cables and the technologies associated with them. Indeed, the initial surge in web usage in the mid 1990s coincides with the commissioning of the first optically amplified transatlantic cable network, TAT12/13 that allowed ready access to information otherwise inaccessible. Similarly, the remarkable growth of social media is supported by the introduction of optical fibres into data centres, allowing their tremendous growth. Exponential growth has been a characteristic of data communications since their first introduction in the 1970's and has been fuelled by the gradual introduction of radical technologies, such as optical amplification, wavelength-division multiplexing and coherent modulation. All of these technologies are today routinely deployed and it is widely acknowledged that fibres are becoming full. The limit to fibre capacity has its origin in the fact that the intense signals are significantly distorted by nonlinearly (a similar effect to overdriving loudspeakers). This distortion limits the maximum amount of information which may be transmitted across and optical fibre link, and unless combated, the nonlinear response will result in a capacity crunch, limiting access to the internet to today's levels. Faced with the ongoing exponential growth in demand, unless these restrictions are lifted many parallel systems will be required, resulting in exponentially increasing energy consumption, until the cost of this resource becomes prohibitive and finally curtails growth. Only one technology, optical phase conjugation (acting like a mirror for colours), has been shown to offer the prospect of supporting continued internet growth without the need for widespread use of multiple fibres and the associated growth in energy consumption. Very much like Newton's Prisms, optical phase conjugation allows the distortion of one fibre (analogous to spectral spreading in Newton's prisms) to be compensated by a second identical fibre. In PHOS, we will - Optimise the devices which perform this conjugation, both in terms of the assessment of fundamental nonlinear materials and in terms of optimised sub-system configuration. - Demonstrate orders of magnitude increase in the capabilities of optical fibres for both practical point-to-point links with non-uniform span lengths and for optical networks with a plethora of diverse routes. - Verify that the use of optical phase conjugation is cost effective, both in terms of reducing the cost of a network deployment compared to existing products and in terms of enhancing the service provided to customers through higher capacity with lower latency. Furthermore, as optical phase conjugation will transform the capabilities of the network, PHOS will work to remove bottlenecks within the network transmitters and receivers, increasing their performance by an order of magnitude, resulting in 10 times faster connections. The approach of compensating impairments in the optical domain, combined with simplified digital signal processing and enhanced exploitation of fibre bandwidth will reduce the cost, size and power consumption associated with providing 10's of Tbit/s of capacity per optical fibre. If successful, PHOS will enable massively increased data capacities from the employment of Optical Phase Conjugation, giving the UK the most advanced optical communication network and a strong position to become a leading supplier of the technology worldwide.

DYNAMOS develops fast (1 ns) and widely tunable (>110 nm) lasers, energy-efficient (~ fJ/bit), broadband (100 GHz) electro-optic modulators, and high-speed (1 ns) broadcast-and-select packet switches as photonic integrated circuits (PICs). DYNAMOS meets the expected outcome objectives and call scope by proposing the development of low energy (few pJ/bit) PICs, which are integrated into modular and scalable subsystems, and subsequently utilized to demonstrate novel data centre networks with highly deterministic sub-microsecond latency to enable maximum congestion reduction, full bisection bandwidth (lower congestion) and guaranteed quality of service while reducing cost per Gbps. The proposed network offers optical circuit switched reconfiguration and guaranteed (contention-less) full-bisection bandwidth, allowing any computational node to communicate to any other node at full-capacity. DYNAMOS builds on recent developments in III-V optoelectronics, thick silicon-on-insulator waveguide technology, and silicon organic hybrid (SOH) modulators. It co-develops the entire ecosystem of transceivers, switches and networks to boost overall performance and to reducing the total cost of data exchange, instead of focusing on the improvement of individual optical links or interfaces. The objectives of DYNAMOS perfectly match the major photonics research & innovations challenges defined in the Photonics21 Multiannual Strategic Roadmap 2021-2027.

Electronically beam-steerable array antennas (phased arrays or smart antennas) at microwave and millimetre-wave (mm-wave) frequencies are extremely important for various wireless systems including satellite communications, terrestrial mobile communications, radars, "Internet Of Things", wireless power transmission, satellite navigations and deep-space communication. Traditionally, beam steering of antenna is achieved by moving the reflector mechanically, which is slow, bulky and not reliable. Phased arrays, which integrate antennas and phase shifter circuits, are an attractive alternative to gimbaled parabolic reflectors as they offer rapid beam steering towards the desired targets and better reliability. Phase shifters are critical components in phased arrays as the beam steering is achieved by controlling phase shifters electronically. A promising research direction to create small, fast, reliable phase shifters with low insertion loss at high frequency is the use of tunable dielectric materials due to its potential of monolithic fabrication of array antennas and circuits. A breakthrough in such materials came recently when we demonstrated that Lead Niobate Pyrochlores PbnNb2O5+n gives the best combination of dielectric constant, tunability and low loss of any known thin film system. Translating these superior materials properties into actual device performance and high-performance electronically beam-steerable arrays antennas at microwave and mm-wave bands are the key aims of this project