The identification and remote detection of energetic materials have become a major issue of dual research, both civil and military, for the Defence and Security of populations in France, on the European continent and overseas. A strong axis of photonics research in this context is the ability to measure the unique spectral signatures of explosives or materials representing a potential threat (e.g., IED - Improvised Explosive Devices), from remote distances larger than 10 meters. Building a prototype for this purpose requires knowledge of some signatures of explosives in a particular spectral range and to transmit appropriate radiations operating in this range with high enough field intensities to interact with the target material and to collect the scattered field. Here, we propose to exploit the terahertz (THz) spectroscopy for the measurement and identification of spectra of explosives having a military interest and those of mimic products (« simulants »). The THz waves, located between the microwaves and infrared waves, are not invasive; they pass through some thin materials and have a high selectivity to the rotational and vibrational transitions of complex molecules including those having the functional groups of explosives. In recent years, many researchers have coupled intense femtosecond laser pulses to produce terahertz field amplitudes greater than the GV/m and being broadband enough (from 1 to 50 THz) to make the junction with the far- and mid-infrared region. In this extended spectral range, many " fingerprints " of explosives are expected. With the novel available high-power laser sources, their identification over long distances in air is nowadays possible. The ALTESSE project proposes an exploratory research on a new technology for emitting THz radiation by using two-color ultrashort laser sources in order to form a remote plasma rendered controllable by the focusing geometry and the optical beam parameters (short focal length or collimated propagation in filamentation regime). The detection part of our device is based on exploiting the second harmonic induced by four-wave mixing (third-order process) between the laser pump, the emitted THz field and a high-voltage electric field, then on performing the spectrum of the collected radiation. This method, called ABCD ("Air-Biased Coherent Detection "), never operated in France, can constitute a significant technological breakthrough in detection and analysis of a rich variety of explosives. To establish the proof of concept of this technology, four partners are involved in the project. A team of experts in high-performance computing (CEA, CELIA) will provide data from numerical simulations predicting the best laser configurations for the generation of THz sources created by plasma. During the first 18 months of the project, the University of Marburg (Germany) will test this new technology for laser-plasma-based THz spectroscopy of simulants detected in both transmission and reflexion geometries. The University of Bordeaux (CELIA) will test the same technology for laser wavelengths operating in the ocular safety domain. The last 18 months of the project will be devoted to install a laser source at the French-German Research Institute of Saint-Louis for the detection of solid explosives (powders, plastics and mixtures) by transmission and reflection, in an authorized area. We propose to record, interpret and complete the databases of many explosives in the THz-infrared band. The success of such a project would pave the way to a maturation stage especially dedicated to remote sensing and offer promising perspectives for the achievement of a demonstrator.

The liquid-liquid transition (LLT) is a rare and intriguing phenomenon is which a single-component liquid transforms into another one via a first-order transition. Owing to its counterintuitive nature, the LLT has intrigued scientists for several years and challenged our perception of the liquid state, for which the notion of polymorphism was long considered impossible. LLTs have been predicted from computer simulations of several systems, and heavily debated in the case of supercooled water. However, our theoretical understanding remains relatively primitive, and there is no theory at present able to predict whether a given system will exhibit a LLT. This is why the experimental realizations reported so far remain scarce, have been made rather accidentally and are often controversial. A recent breakthrough was made by the present proposer consortium, with the experimental discovery of such a LLT in compressed liquid sulfur, and the first-ever evidence of a liquid-liquid critical point (LLCP) ending the transition line. Such a LLCP has long been searched in water but to date impossible to reach by experiment. Located at about 2.15 GPa-1035 K, the LLCP in sulfur can be easily approached by experiment, which opens brand new perspectives to the field. The general objective of this project is to advance our understanding of LLTs, by obtaining accurate data sets from experiments and computer simulations that will form a solid basis to extract the systematics of LLTs, and aid the emergence of predictive theories. For this, we propose to study several systems which are representative of different types of materials, over a large range of pressure and temperature conditions (0-150 GPa, 300-3000 K), and using several x-ray and optical diagnostics available at the 3 partners’ sites. The first part of the project (Tasks 1 and 6) will focus on the two systems for which a LLT is now well established, phosphorus and sulfur. We will study for the first time the critical phenomena and universality class of the LLCP in sulfur using innovative small-angle x-ray scattering (SAXS) experiments in the diamond anvil cell (DAC). We will also determine whether a LLCP exists in phosphorus through x-ray measurements of the density jump along the LLT line. A better understanding of the microscopic nature of the low-density and high-density liquid phases and of the driving mechanism of the LLT in both S and P will be achieved through experiments and simulations. Finally, we will investigate their melting lines in the vicinity of the LLT and whether the two-state model is compatible with thermodynamic data for these two systems. In the second part of the project, we will extend our investigations to other systems which are promising candidates for a LLT, as suggested by computer simulations or previous experimental results. Specifically, we will focus on two network liquids (Task 2), B2O3 and AsS, the molecular liquids of nitrogen, carbon dioxide, hydrogen (Task 3), and the liquid alkali metals (Li, Na, K) (Task 4). For B2O3 and AsS, the LLT is expected below a few GPa and similar studies as those described above for sulfur and phosphorus will be carried out. For the molecular and alkali liquids, the expected location of the LLT resides at pressures from 20 to 150 GPa, which requires the use of smaller samples compressed in the DAC. The present proposers have developed new techniques in the framework of the ANR project MOFLEX which have made possible structural and vibrational studies of liquids composed of light elements in the DAC up to megabar pressures through x-ray diagnostics combined to Raman and Brillouin spectroscopies, which will be put to profit for this project. Additional technical developments (Task 5,) such as high P-T SAXS experiments, will be undertaken during the project to complement or enable new types of measurement under high P-T.

ANR PROFIL (Broadband PROfessional Mobile Radio based on FILter Bank Multicarrier modulation) project aims at contributing to PMR (Professional Mobile Radio) networks evolutions. These networks, which transmit low data bit rate services for public safety and mission critical applications (usually voice), are asked to meet new requirements for larger bit rate transmission (video). Nevertheless these future PMR Broadband services are required (at first) to share channel bandwidths with current (narrow band) PMR services and to access free spaces between these PMR narrow bands. As a consequence a deep study has to be done in order to keep quality of service (especially of currently deployed PMR services) and to meet new requirements. As a top world-wide leader in PMR, CASSIDIAN proposes multi-carrier modulation for broadband PMR to combat time and frequency selective channels. But regular OFDM modulation is well known to have poor frequency localization due to time rectangular pulses. This is the reason why FBMC (Filter Bank MultiCarrier) modulation is viewed as a serious candidate for next PMR networks generation for the following reasons: no guard interval, very low side lobes and full capacity. Moreover sub channels can be grouped into independent blocks that feature is crucial for scalability and dynamic access. As a consequence PROFIL project objective is to propose a study on FBMC modulation for broadband PMR taking into account both the need of coexistence between PMR networks and performance requirements. The outline of the project is firstly to propose scenarios to define key parameters (number of carriers, pilot scheme, symbol length, etc.) of FBMC in PMR context and secondly to feed works on synchronization and equalization. In parallel, studies on coexistence will be led both on PHY and MAC layers. A demonstrator will be provided at the end of the project so as to illustrate the benefits of FBMC modulation in terms of coexistence and performance. A task will be dedicated to dissemination (publications in conferences and journal) and standardization (particularly at ETSI group) to promote FBMC for broadband PMR.

In May 2011, IRAM (Institut de Radioastronomie Millimétrique) issued a call for tender for the next generation continuum instrumentation of the 30-m telescope at Pico Veleta (Spain). The NIKA (New IRAM KIDs Arrays) consortium answered with a detailed proposal to build a large-format, dual-color (150GHz = 2mm and 240GHz = 1.25mm) camera. This proposal was examined by the IRAM Scientific Advisory Committee who has recently issued a positive recommendation for the NIKA camera. The instrument will be based on the new and extremely promising KIDs (Kinetic Inductance Detectors) technology. The technological program is led by French researchers at the Institut Néel and LPSC (Grenoble). The French part of the collaboration is completed by IPAG (Grenoble), IAS (Orsay), CEA-IRFU (Saclay) and IRAP (Toulouse). IRAM-Grenoble is actively participating to the project, contributing with 50% co-financing and their expertise in the field of detectors design/fabrication, electronics and data analysis. At the international level, this French consortium will collaborate with the University of Cardiff (UK), the Netherlands Institute for Space Research – SRON and The University of Roma La Sapienza (Italy). The international collaborators will provide in particular, on independent funding, the optical filters and the beam splitter. The NIKA camera will be based on a prototype instrument already tested at the IRAM 30-m telescope in 2009, 2010 and 2011. These successful technical/scientific runs allowed for the first time to assess the viability of the KIDs technology for ground-based mm-wave observations. In particular, the 2011 dual-band prototype exhibited a state-of-the-art performance at 150 GHz. The instrument will incorporate a continuous close-cycled dilution refrigerator with a base temperature of 100 mK, cold reimaging optics and filters designed to sample a 6 arc minute field of view simultaneously in at least 2 channels centered at wavelengths of 1.25 and 2 mm. The baseline detector focal plane units will consist of arrays of KIDs with a pixel spacing of 0.75 f*lambda giving approximately 1000 detectors at 2 mm and 3000 detectors at 1.25 mm. These detectors will be read out with a maximum of 16 cold amplifiers, and the same number of coaxial cables pairs. On top of that, the implementation of a “Polarization Channel” allowing linearly polarized continuum emission to be measured in at least the 1.2 mm band is being planned as a future upgrade. The implementation of a third imaging band in the sub-mm range (850 micron) is also envisaged as a second-priority upgrade. In the present proposal, we request ANR support for the construction of the baseline instrument (dual-band, pure imaging, as stated by IRAM in their call). Funding for the “Polarization Channel” upgrade has already been obtained by CEA-IRFU (Saclay) as part of an ERC European contract. The baseline instrument will be designed to be fully compatible with both upgrades. The duration of this ANR program is three years, mainly dedicated to an intense instrumental development: cryostat fabrication, detectors and electronics design, fabrication and testing. The last semester is mainly characterized by the instrument commissioning at the Pico Veleta telescope. At the end of the ANR project, the NIKA camera will become a powerful facility instrument (e.g. the gain in mapping speed compared to the previous generation continuum instrument is 40-100) which will benefit the entire community of astronomers using IRAM.

The developments of calculation methods for the simulation have long since become a major issue for our industries (civil or military) for product design and understanding of physical phenomena involved. Among these developments, those relating to the methods of explicit approximate calculation of complex objects of electromagnetic radiation have the advantage: -to simplify the calculation and make it faster than a conventional numerical method and to optimize existing hybridization methods. -to allow easier parameterization of the influence of each contributor according to its geometry, its electrical characteristics, and enlightenment, -to facilitate the understanding, prediction and diffraction behavior analysis. These methods have been the subject of TREMA project (REcherche work on ME Analytical Modeling and Applications) from January 2012 to January 2015 on three subjects, First task: calculation of electromagnetic radiation of a small size 3D element on an imperfect conductive pattern, 2nd task: Calculation of near field electromagnetic coupling between two antenna elements in an object imperfectly conducting, 3rd task: Developments for quick calculation of the Near Field Optical Physics on large structures, where innovative solutions have been determined. Thus, the original analytical and hybrid methods that were defined during the ASTRID TREMA, can be integrated into existing computer codes that they are accurate (ASERIS) or approximate (Optical Physics in SERMAT MBDA methods summing Gaussian beams for code celum) to improve their performance calculation. They will allow codes to be used with fewer resources in order to easier setting next illumination, the geometry and electrical properties of the object studied. The proposed work should enable optimization opportunities (geometric shapes, materials ...) which are difficult to purely digital classics approaches. In this context, we propose to perform: -in Task 1: integration and development of the original hybrid method defined in the ASTRID TREMA for a simple determination of the influence on the radiated field of the coupling between antennas of diffractive elements, according to the location and characteristics thereof; then analyzing the performance obtained in comparison with other methods, depending on the case of selected validation, -in Task 2: a generalization of the original method was developed and validated during the ASTRID TREMA concerning the fields diffracted by a surface defect, for now consider the case of multiple cavities connected small openings , 2D and 3D, with and without materials. -in Task 3: implementation in the codes of the method for calculating the scattered fields in the near field of the Physical Optics approximation by a surface of small curvature and large dimensions, which have been developed and validated in the ASTRID TREMA and its use for the improvement of asymptotic methods of propagation and diffraction of Gaussian beams.