As the communication bandwidth and the bandwidth density scale with Moore’s law, the reach-capability of copper links shrinks, while the optical solutions at very high data rates (enhanced by Wavelength Division Multiplexing -WDM-) are costly and power greedy. 850nm Vertical Cavity Surface Emitting Laser (VCSEL) links dominate at distances from 1 to a few 100 meters, where they provide a significant cost and power benefit, but this solution does not scale with the interconnect needs of mass market applications, such as high performance computer applications and data center applications. The PICSEL project focuses on the development of a new Silicon-Photonics hybrid III/V-on-Si-laser source. The PICSEL source is a long-wavelength (1.5µm to 1.3µm) Vertical Cavity Laser, where bottom and top mirrors are replaced by silicon Photonic Crystal grating-Mirrors (PCM), 1-making the cavity shorter, 2-enabling precise frequency laser emission according to accurately-controlled wavelengths through the lithographic definition of the filling factor of the crystal grating-mirror, and, 3-allowing edge-coupling of the light into a waveguide. With the proposed source, called VCSEEL for “Vertical Cavity Surface and Edge Emitting Laser”, the PICSEL project addresses fabrication cost, bandwidth density (high capacity, high integration density) and power efficiency issues: - Fabrication cost: the PICSEL laser source will be developed in cost-effective mass-scale CMOS front-end fabrication lines; - High capacity: the VCSEEL source is expected to be faster than conventional VCSELs thanks to shorter cavity lengths, thus it has the potentiality to be modulated at higher bitrates; it also offers scalability of the bandwidth density, thanks to its capability to “edge-emit” light into a silicon waveguide, thus enabling WDM-multiplexing of VCSEEL-array into a single waveguide; - High integration density: the aforementioned WDM capability of edge-emission of VCSEELs enables higher integration density, as several (n>4) channels using several VCSEEL lasers can be designed and fabricated on a same chipset, when using an integrated multiplexer (such as AWG), nx10Gbps or nx25Gbps chip-sets will considerably increase the integration density thus substantially decrease the equipment footprint. - Power efficiency: sub milli-amperes threshold current and 20% wall-plug efficiency typical for VCSEL source, are expected. This novel technology paves the way for a new generation of VCSEL devices which should result in a fully successful replacement of the present VCSEL photonics, by employing existing CMOS processing capability, allowing for a high-throughput mass fabrication. Also, the complete renewal of physical concepts will result in the broadening of accessible functionality and application spectra and grants solid perspectives of a promising industrial potential, whose far-reaching future developments can hardly be appreciated in full as today. This later upstream aspect will be addressed in PICSEL and a specific functionality will be demonstrated: the free-space beam steering of arrays of VCSEELs. With a complementary and vertically-integrated consortium covering the whole food-chain, including design, fabrication, and test and with CMOS-compatible front-end processes and III-V-fab available back-end processes, the project PICSEL paves the way for a 3-year-term industrial solution. In addition, “upstream” concepts, enabled by the proposed laser architecture, will be investigated as they are expected to offer enhanced transmission and processing performances.

Non-equilibrium plasmas generally exhibit phase space anisotropies, for instance in the case of particle beams traversing background plasmas or in interpenetrating plasma flows – common configurations in space and laboratory plasmas. This results in the spontaneous growth of micro- instabilities, that is, self-amplified electromagnetic and current fluctuations building up at kinetic scales, and leading to energy and momentum transfers between the plasma constituents. In this project, we propose to exploit state-of-the-art laser and accelerator systems, combined with novel precision diagnostics, to study beam-plasma systems prone to relativistic streaming instabilities, similar to those arising in high-energy astrophysics. The required physical conditions will be achieved by means of (i) all-optical setups based on femtosecond relativistic laser-solid interactions probed by external wakefield-driven electron bunches, and (ii) high-density, GeV-level accelerator electron beams interacting with solid or gas targets. Supported by advanced numerical simulations, these highly resolved experiments will offer unprecedented insight into the dynamics and interplay of the competing instabilities, in a broad parameter range in terms of beam energy, fractional beam density and plasma collisionality. Notably, the experiments planned at the upgraded FACET-II facility at the SLAC National Accelerator Laboratory (USA) will allow plasma instabilities to be explored at beam energies and currents orders of magnitude increased over previous works. As a consequence, the instability-driven electromagnetic fields should be strong enough to induce intense synchrotron-type gamma-ray flashes, which we will intend to characterize for the first time. These laboratory investigations will be complemented by prospective studies of even greater astrophysical relevance, involving ultrarelativistic electron-positron beams envisioned at next- generation multi-petawatt laser or accelerator facilities.

We are requesting the funding of an R&D program aiming at characterizing the use of an existing technology in high-energy physics (HEP), a time projection chamber (TPC), for a new application, the high-precision detection of high-energy photons, and in particular of their polarization fraction. The ultimate goal, on a longer term, is the launch of such a detector in space to study gamma photons from cosmic sources. We are developing a novel concept for a gamma-ray detector based on a TPC, which will be: - the first polarimeter for cosmic gamma rays in the energy range MeV-GeV, such as those emitted by active galaxy nuclei (AGN), gamma-ray bursts (GRB) and pulsars. Polarimetry is performed by the analysis of the angular properties of triplet conversion events (gamma e- -> e+e- e-), that are reconstructed in the TPC. - a telescope with an angular resolution improvement of one order of magnitude over previous telescopes in this energy range. This instrument allows to fill the sensitivity gap between energy ranges in which the Compton telescopes (0.01 - 5 MeV) and telescopes using pair conversion in a high-Z converter (> 0.1 GeV) are most sensitive. - A dead-time-free GRB detector, since it is based on a TPC. The realization of the proposed ground-based characterization is a prerequisite for a future spatial mission. In addition to the characterization of a prototype exposed to a linearly polarized gamma-ray beam from an accelerator, two important deliverables will be: - the first experimental validation of polarization asymmetries at low energy, the knowledge of which is needed for polarized gamma-ray astronomy but also to validate experimentally a number of assumptions made in the theoretical computations based on QED. - the implementation of an exact Monte Carlo (MC) generator of conversion events in the HEP simulation software Geant4, i.e. a generation of the full 5D probability density function (PDF).

Using existing traditional Euro-Mediterranean know-how and recent developments in the field of biotechnology of aquatic microorganisms, our project aims at studying, designing, and disseminating a local circular strategy for rural wastewater treatment with minimal renewable energy input that will supply valuable goods and services (clean irrigation water, fertilizers, phytostimulants, etc…) to vulnerable rural communities. The intensive utilization of chemical fertilizers, pesticides, and herbicides for agriculture, together with largescale livestock farms, in the Euro-Mediterranean area, are contributing to the pollution of rural waters (relevant to nitrogen contamination). However, rural wastewater treatment in Euro-Mediterranean rural areas faces significant barriers such as high-cost, ineffective processes, or managing capacity. Conventional wastewater treatment processes such as activated sludge system are not applicable due to high investment and operation costs. Alternative processes (constructed wetlands and reed bed systems) exist but they are low efficient, and they do not allow the production of quality biomass that can add an economic value to the process and reduce costs. The WABA project principal goal is to develop an alternative eco-friendly and sustainable wastewater treatment process for rural areas based on a microalgae-bacteria consortium. The potential of microalgae for bioremediation of wastewater has recently received considerable interest. Compared to physical and chemical treatment processes, algae based treatment can potentially achieve nutrient removal in a less expensive and ecologically safer way with the added benefits of resource recovery and recycling. However, no study has analyzed the energetic benefits and techno-economic limitations of this concept in the context of Euro-Mediterranean rural areas. Bacteria-algae consortia can enjoy most of metabolic features of both components, and are potentially economically sustainable, thanks to their capacity to operate with minimal natural inputs such as sunlight, atmospheric CO2 and nutrients from wastewaters. Thus, this system can be energetically efficient, and ecologically friendly. The project will study the relationship between algae and bacteria to understand how we can improve this partnership and maximize non-energy intensive treatments of rural wastewater, combined with the production of algae-based agronomical useful products. Our preliminary data show that specific microbial consortia are able to uptake nitrogen better than algae on their own, thereby increasing removal nitrogen from wastewater, and decreasing eutrophication index. We will study the relationship between these organisms to understand and improve the removal of nitrogen and other pollutants. These consortia will be then fed with wastewater and the pollutant removal efficiency evaluated. A novel process will be developed to combine optimum consortia growth and wastewater bioremediation. Robust analytical methods based on FTIR spectroscopy will be developed to assess the contribution of the various components to the consortium, and further determine and monitor the biomass quality. The biomass generated will be evaluated as biofertilizer and biostimulant in a local agriculture context. Importantly, we will also perform optimization studies in order to improve the energy efficiency of the method and reduce the costs. Finally, the impact on rural economy will be assessed in two case studies (France and Morocco), and compared to current remediation systems

Unveiling the physical conditions around black holes is one of the major astrophysical challenges of the 21st century. Indeed we are still at the dawn of black hole astrophysics and very little about these objects is understood: what are the geometry, dynamics and energetics of the accretion flow onto the black hole? How can accretion of material onto the hole be simultaneously intimately related to violent relativistic ejecta and/or powerful self-confined persistent jets? What are the processes at the origin of the fascinating hysteresis cycles observed in some X ray binaries? These unsolved and puzzling issues are at the heart of this ANR2012-CHAOS proposal. It is focused on Black-Hole X-ray Binaries (hereafter BHB ) as they are actually the best candidates for such studies, their complex multi-wavelength behaviour occurring on timescales that can be handled very well (i.e. minutes to months). This project is the natural development of a precedent theoretical and numerical ANR “Jeunes Chercheurs” with now the additional ambition of getting closer to observations, in spite of the major criticism made upon our ANR 2011 submission. Indeed, collaborating with experts in multi-wavelength observations is crucial for the present project for two reasons. First, a precise knowledge of the global observational characteristics of microquasars is needed to drive the theoretical and numerical developments. Such knowledge is unaccessible for non-experts. Second, a direct comparison with observations is essential to validate/invalidate our theoretical framework. Within the present project, each field of expertise (dynamics, radiation, observation) will first improve existing tools and/or develop new ones: (i) time dependent accretion disc models, where ejection is consistently taken into account, will be designed; (ii) multi-zones, radiative and kinetic simulation codes will be developed and (iii) the most up-to-date broad band (from radio to gamma-rays) database of BHB properties will be set-up, coupled with opening of new observing windows. Then, these tools will be brought together in an unprecedented effort within the community. Thus, besides the development of new simulation tools that can be applied to many different astrophysical problems, we will be able to produce synthetic Spectral Energy Distribution for these sources, analyse and predict their timing evolution, and directly compare with the most complete and stringent set of multi-wavelength data that we will produce. By gathering together well-known experts in observation, radiation processes and theory of accretion-ejection processes around compact objects, this project aims at strengthening the French BHB community. It will not only strengthen our leadership in the field but will also significantly enhance our knowledge on the accretion-ejection processes in BHB and, more generally, in all types of compact accretors.