Compound semiconductor solar cells are providing the highest photovoltaic conversion efficiency, yet their performance lacks far behind the theoretical potential. This is a position we will challenge by engineering advanced III-V optoelectronics materials and heterostructures for better utilization of the solar spectrum, enabling efficiencies approaching practical limits. The work is strongly motivated by the global need for renewable energy sources. To this end, AMETIST framework is based on three vectors of excellence in: i) material science and epitaxial processes, ii) advanced solar cells exploiting nanophotonics concepts, and iii) new device fabrication technologies. Novel heterostructures (e.g. GaInNAsSb, GaNAsBi), providing absorption in a broad spectral range from 0.7 eV to 1.4 eV, will be synthesized and monolithically integrated in tandem cells with up to 8-junctions. Nanophotonic methods for light-trapping, spectral and spatial control of solar radiation will be developed to further enhance the absorption. To ensure a high long-term impact, the project will validate the use of state-of-the-art molecular-beam-epitaxy processes for fabrication of economically viable ultra-high efficiency solar cells. The ultimate efficiency target is to reach a level of 55%. This would enable to generate renewable/ecological/sustainable energy at a levelized production cost below ~7 ¢/kWh, comparable or cheaper than fossil fuels. The work will also bring a new breath of developments for more efficient space photovoltaic systems. AMETIST will leverage the leading position of the applicant in topical technology areas relevant for the project (i.e. epitaxy of III-N/Bi-V alloys and key achievements concerning GaInNAsSb-based tandem solar cells). Thus it renders a unique opportunity to capitalize on the group expertize and position Europe at the forefront in the global competition for demonstrating more efficient and economically viable photovoltaic technologies.

Sounds carry a large amount of information about our everyday environment and physical events that take place in it. For example, when a car is passing by, one can perceive the approximate size and speed of the car. Sound can easily and unobtrusively be captured e.g. by mobile phones and transmitted further – for example, tens of hours of audio is uploaded to the internet every minute e.g. in the form of YouTube videos. However, today's technology is not able to recognize individual sound sources in realistic soundscapes, where multiple sounds are present, often simultaneously, and distorted by the environment. The ground-breaking objective of EVERYSOUND is to develop computational methods which will automatically provide high-level descriptions of environmental sounds in realistic everyday soundscapes such as street, park, home, etc. This requires developing several novel methods, including joint source separation and robust pattern classification algorithms to reliably recognize multiple overlapping sounds, and a hierarchical multilayer taxonomy to accurately categorize everyday sounds. The methods are based on the applicant's internationally recognized and awarded expertise on source separation and robust pattern recognition in speech and music processing, which will allow now tackling the new and challenging research area of everyday sound recognition. The results of EVERYSOUND will enable searching for multimedia based on its audio content, which is not possible with today's technology. It will allow mobile devices, robots, and intelligent monitoring systems to recognize activities in their environments using acoustic information. Producing automatically descriptions of vast quantities of audio will give new tools for geographical, social, cultural, and biological studies to analyze sounds related to human, animal, and natural activity in urban and rural areas, as well as multimedia in social networks.

The next frontier in photonics is to achieve dynamic and externally tunable materials that allow for real-time, on-demand control over optical responses. Light is in many ways an ideal stimulus for achieving such control, and PHOTOTUNE aims at devising a comprehensive toolbox for the fabrication of light-tunable solid-state photonic structures. We harness light to control light, by making use of photoactuable liquid-crystal elastomers, which display large light-induced deformations through coupling between anisotropic liquid-crystal order and elasticity brought about by the polymer network. We will take liquid-crystal elastomers into a new context by intertwining photomechanics and photonics. Specifically, PHOTOTUNE is built around the following two objectives: (i) Tunable photonic bandgaps and lasing in photoactuable layered structures: The aim is to take photomechanical materials into the scale of optical wavelengths and utilize them in thickness-tunable liquid-crystal elastomer films. Such films will be further integrated into layered structures to obtain photonic crystals and multilayer distributed feedback lasers whose properties can be tuned by light. (ii) Photomechanical control over plasmonic enhancement on nanostructured elastomeric substrates: Fabrication of metal nanostructures on substrates that can contract and expand in response to light comprises a perfect, yet previously unexplored, nanophotonic platform with light-tunable lattice parameters. We will apply such tunable photoelastomeric substrates for surface-enhanced Raman scattering and phototunable nonlinear plasmonics. We expect to present a wholly new technological toolbox for tunable optical components and sensing platforms and beyond: The horizons of PHOTOTUNE are as far-reaching as in studying distance-dependent physical phenomena, controlling the speed of light in periodic structures, and designing actively-tunable optical metamaterials.