The sensing, processing and transport of information is at the heart of modern life, as can be seen from the ubiquity of smart-phone usage on any street. From our interactions with the people who design, build and use the systems that make this possible, we have created a programme to make possible the first data interconnects, switches and sensors that use lasers monolithically integrated on silicon, offering the potential to transform Information and Communication Technology (ICT) by changing fundamentally the way in which data is sensed, transferred between and processed on silicon chips. The work builds on our demonstration of the first successful telecommunications wavelength lasers directly integrated on silicon substrates. The QUDOS Programme will enable the monolithic integration of all required optical functions on silicon and will have a similar transformative effect on ICT to that which the creation of silicon integrated electronic circuits had on electronics. This will come about through removing the need to assemble individual components, enabling vastly increased scale and functionality at greatly reduced cost.

The Scottish Doctoral Training Centre in Condensed Matter Physics, known as the CM-DTC, is an EPSRC-funded Centre for Doctoral Training (CDT) addressing the broad field of Condensed Matter Physics (CMP). CMP is a core discipline that underpins many other areas of science, and is one of the Priority Areas for this CDT call. Renewal funding for the CM-DTC will allow five more annual cohorts of PhD students to be recruited, trained and released onto the market. They will be highly educated professionals with a knowledge of the field, in depth and in breadth, that will equip them for future leadership in a variety of academic and industrial careers. Condensed Matter Physics research impacts on many other fields of science including engineering, biophysics, photonics, chemistry, and materials science. It is a significant engine for innovation and drives new technologies. Recent examples include the use of liquid crystals for displays including flat-screen and 3D television, and the use of solid-state or polymeric LEDs for power-saving high-illumination lighting systems. Future examples may involve harnessing the potential of graphene (the world's thinnest and strongest sheet-like material), or the creation of exotic low-temperature materials whose properties may enable the design of radically new types of (quantum) computer with which to solve some of the hardest problems of mathematics. The UK's continued ability to deliver transformative technologies of this character requires highly trained CMP researchers such as those the Centre will produce. The proposed training approach is built on a strong framework of taught lecture courses, with core components and a wide choice of electives. This spans the first two years so that PhD research begins alongside the coursework from the outset. It is complemented by hands-on training in areas such as computer-intensive physics and instrument building (including workshop skills and 3D printing). Some lecture courses are delivered in residential schools but most are videoconferenced live, using the well-established infrastructure of SUPA (the Scottish Universities Physics Alliance). Students meet face to face frequently, often for more than one day, at cohort-building events that emphasise teamwork in science, outreach, transferable skills and careers training. National demand for our graduates is demonstrated by the large number of companies and organisations who have chosen to be formally affiliated with our CDT as Industrial Associates. The range of sectors spanned by these Associates is notable. Some, such as e2v and Oxford Instruments, are scientific consultancies and manufacturers of scientific equipment, whom one would expect to be among our core stakeholders. Less obviously, the list also represents scientific publishers, software houses, companies small and large from the energy sector, large multinationals such as Solvay-Rhodia and Siemens, and finance and patent law firms. This demonstrates a key attraction of our graduates: their high levels of core skills, and a hands-on approach to problem solving. These impart a discipline-hopping ability which more focussed training for specific sectors can complement, but not replace. This breadth is prized by employers in a fast-changing environment where years of vocational training can sometimes be undermined very rapidly by unexpected innovation in an apparently unrelated sector. As the UK builds its technological future by funding new CDTs across a range of priority areas, it is vital to include some that focus on core discipline skills, specifically Condensed Matter Physics, rather than the interdisciplinary or semi-vocational training that features in many other CDTs. As well as complementing those important activities today, our highly trained PhD graduates will be equipped to lay the foundations for the research fields (and perhaps some of the industrial sectors) of tomorrow.

Current applications for semiconductor lasers are wide ranging and pervade every aspect of life. Indeed, in the developed world, most people already own several lasers and gain the benefit of many more. With every new technology, this proliferation is set to continue. Most importantly, the laser enables the internet age since all data transmitted around the globe is carried as flashes of laser light. As a consequence most people in the developed world have come to depend on many lasers during a typical day. The reduction in their cost of ownership is therefore of critical importance to the extension of these benefits to the developing world and also bringing new benefits to us all. The potential future applications of photonics are seemingly unlimited, with new technologies and applications continuing to emerge. The key advantage of a semiconductor laser is that if an application has sufficiently large volume, the cost of the semiconductor laser is very low. The DVD player is a good example -with the laser costing a few pence each. The semiconductor laser therefore enables new technologies, devices and processes to be commercialized. However, semiconductor lasers must be able to generate the required "flavour" of light; i.e. the correct wavelength, spectral width, power, polarization, beam shape, etc. Some of the fundamental parameters of a semiconductor laser may be controlled by the design and choice of materials, e.g. wavelength, spectral purity (line-width). However, using current technologies the polarization and beam profile are generally fixed at manufacture and may only be subsequently altered by extrinsic optical components. This introduces additional cost (increasing the environmental impact) and reduces the overall efficiency and usefulness of the device. For future engineers and scientists it would be ideal if there were complete control of the output from a semiconductor laser, providing unlimited possibilities in terms of future applications. The alteration of matter on the scale of the wavelength of light is known to allow the control of the optical properties of a material. Even the laser in something as simple as a mouse incorporates a number of such technologies. We will develop novel nano-scale semiconductor fabrication to modify light-matter interaction and engineer the control of the polarization and form of a laser beam. Our work will realise a volume manufacturable photonic crystal surface emitting laser (PCSEL) for the first time. The nano-scale photonic crystal is responsible for controlling the properties of the laser. It is simply a periodic pattern similar in size to the light itself, a natural example of this periodic patterning produces the blue colour in some butterfly wings, or the iridescence of opal. In our case, every detail of the photonic crystal will be modeled, understood and optimized to control the properties of the laser to meet a range of needs. Lasers will be designed to exhibit almost zero divergence and will also allow, for the first time, the electronic control of divergence and polarization and allow the direct creation of custom engineered beam profiles and patterns. The realization of high efficiency, area scalable high power lasers with ideal beam profiles will contribute to reduced energy consumption in the manufacture of laser devices, and in their cost of ownership. The technologies developed will allow the ultimate in design control of future optical sources, hopefully limiting laser applications only to the imagination. Once successful, such devices will displace existing lasers in established commercial photonics and enable many more emerging application areas. This will be made possible by introducing both new functionality to laser devices and reducing the cost of existing products. We will develop this technology alongside physical understanding and device engineering, liaising closely with world-leaders in the volume manufacturer of such devices.

A Centre for Innovative Manufacture in Laser-based Production Processes is proposed. This Centre will exploit the unique capabilities of laser light to develop new laser-based manufacturing processes, at both micro and macro levels, supported by new laser source, process monitoring and system technologies. The past 25 years has seen industrial lasers replace many 'conventional' tools in diverse areas of manufacture, enabling increased productivity, functionality and quality, where for example laser processing (cut/join/drill/mark) has revolutionised automotive, aerospace and electronics production. However the penetration of laser technology into some areas such as welding and machining has been less than might have been anticipated. But recently there has been a significant 'step change-opportunity' to take laser-based processing to a new level of industrial impact, brought about by major advances in laser technology in two key areas: (i) A new generation of ultra-high quality and reliability lasers based around solid state technology (laser diode and optical fibre) has evolved from developments in the telecoms sector. These lasers are leading to systems with very high levels of spatial and temporal controllability. This control, combined with advanced in-process measurement techniques, is revolutionising the science and understanding of laser material interactions. The result of this is that major improvements are being made in existing laser based processes and that new revolutionary processes are becoming viable, e.g. joining of dissimilar materials. (ii) A new generation of high average power laser technologies is becoming available, offering controllable trains of ultrashort (picosecond and femtosecond) pulses, with wavelengths selectable across the optical spectrum, from the infrared through to the ultra-violet. Such technology opens the door to a whole range of new laser-based production processes, where thermal effects no longer dominate, and which may replace less efficient 'conventional' processes in some current major production applications. These new developments are being rapidly exploited in other high-value manufacturing based economies such as Germany and the US. We argue that for the UK industry to take maximum advantage of these major advances in both laser material processing and machine technology there is an urgent requirement for an EPSRC Centre for Innovative Manufacturing in Laser-based Production Processes. This will be achieved by bringing together a multi-disciplinary team of leading UK researchers and key industry partners with the goal of exploiting 'tailored laser light'. Together with our industrial partners, we have identified 2 key research themes. Theme A focuses on Laser Precision Structuring, i.e. micro-machining processes, whilst Theme B is focused on joining and additive processes. Spanning these themes are the laser based manufacturing research challenges which fall into categories of Laser Based Production Process Research and Laser Based Machine Technologies, underpinned by monitoring and control together with material science. Research will extend from the basic science of material behaviour modelling and laser-material interaction processes to manufacturing feasibility studies with industry. The Centre will also assume an important national role. The Centre Outreach programme will aim to catalyse and drive the growth of a more effective and coherent UK LIM community as a strong industry/academia partnership able to represent itself effectively to influence UK/EU policy and investment strategy, to promote research excellence, and growth in industrial take-up of laser-based technology, expand UK national knowledge transfer and marketing events and improve the coordination and quality of education/training provision.

Quantum technologies exploit the exotic properties of nature described by quantum mechanics to deliver devices with unprecedented speed, accuracy or completely new functionalities. Quantum cryptography is one such technology: communication whose security is guaranteed by fundamental laws of quantum mechanics. The implementation of quantum cryptography relies on the ability to generate very low intensities or even single photons of light on demand . Several different physical systems have been used to generate single photons, but very few of them are suitable for commercial production. An ideal single photon source should be fast, cheap and efficient, operate at room temperature, and emit photons at the wavelengths used in existing optical-fibre telecoms networks. A practical single photon source is expected to be somewhat like a type of semiconductor laser diode called a vertical cavity surface emitting laser (VCSEL ). We will assess the feasibility of mass-producing low-cost single-photon sources in the form of single-photon light emitting diodes (SPLEDs). These will exploit the unique properties of semiconductor nanostructures called self-assembled quantum rings, which we have recently used in novel VCSELs that operate at very low currents and at temperatures up to 110°C.