Mid-infrared free-space absorption spectrometers have demonstrated label-free and real-time detection of multiple chemical and biological substances with an outstanding precision and versatility. However, they are bulky and high-cost, precluding their use in widespread high-volume applications. The MIR-Spec project will address these limitations by developing innovative silicon on-chip mid-infrared absorption spectroscopy sensors. The ground-breaking concept is to use subwavelength silicon nano-structures to develop a novel platform that leverages the wide transparency (up to ~8 µm wavelength) and large-volume fabrication processes of silicon, leading to significant breakthroughs in sensing applications. The MIR-Spec project is a “Projets de recherche collaborative - entreprises (PRCE)”, which gathers an academic research group (C2N), a Si foundry (STMircroelectronics) and an end-user (MirSense).

This project aims at developing a new type of MEMS magnetometer based on the measurement of the frequency variation of a micro resonator on which is deposited a thin layer of magnetic ferromagnetic material. This new concept of vibrating micro-magnetometer allows a favorable compromise between performance and miniaturization/power consumption. It will meet the requirements of new dual and demanding applications of magnetometry, such as the improvement of low cost inertial measurement units for indoor navigation and the navigation of drones or missiles, or the monitoring of areas by sensor networks. An ASTRID project conducted between ONERA, SYSNAV and the IEF between 2015 and 2018 has made it possible to develop the various technological bricks constituting the magnetometer, as well as the associated calibration bench: - an original configuration of ferro / anti ferro magnetic thin film stacks has been designed, realized and validated experimentally, - a complete model of the resonator including the effect of thin magnetic layers has been developed (analytical model and finite element simulations) and exploited to design an original torsional vibrating resonator configuration. Several resonators were made and tested in the ONERA clean room. - An automated magnetometer calibration bench has been designed and partly realized. At the end of the project, first complete prototypes of magnetometers were realized and the first characterizations carried out. They consist of two miniature resonators on which a stack of thin magnetic layers have been deposited, these two resonators are integrated in a vacuum box and connected to an electronic oscillation circuit. The measurements carried out validated the feasibility of the sensor as well as the possibility of achieving the specified performances. The aim of the ASTRID Maturation project is, on the one hand, to optimize the various existing technological bricks: optimization of the geometry of the magnetic strips deposited on the resonator (without changing the already optimal deposition process), optimizing the configuration of the resonator, based on the results of characterization of the first resonator, and the modeling tools developed, optimize the packaging and layout of the electronic circuits in order to achieve a prototype closer to the final sensor,finalize the design of the automated measuring bench, make it and use it to calibrate and characterize the final prototypes. These optimization steps will precede a phase of realization and characterization of complete prototypes of sensor in representative environment. This will allow to mature the TRL 4 obtained at the end of the ASTRID project, up to TRL 6. The preparation of the pre-industrialization phase will also be carried out with the precise definition of the methods of realization and calibration of the magnetometers as well as the definition of the industrial assembly.

The progress of nanotechnologies has triggered the emergence of many photonic artificial structures: photonic crystals, metamaterials, plasmonic resonators. Recently the intriguing class of PT-symmetric devices– referring to Parity-Time symmetry – has attracted much attention. Their distinctive feature is that the refractive index profile of the structures is complex-valued due to the gain and/or loss, which are spatially separated in the system. They have special properties such as one-sided reflection and exceptional points, i.e. remarkable singularities, in the evolution of propagation constants of the relevant modes. Apart from fundamental research motivations, the tremendous interest in these artificial systems is strongly driven by the practical functionalities that can be achieved by modulating the values of gain and loss in such structures. Several academic reports of PT-symmetric laser structures that incorporate a loss grating or a loss section have been shown to display new functions that are directly related to the specific arrangement of gain and losses, well beyond the basic compensation. So the concept is mature enough for attempting its practical use in real-world applications. The PARTISYMO project aims at erecting an ambitious bridge between the novel fundamental physics concept of PT-Symmetry, and a new generation of devices for integrated optics. We identified two key generic advantages to work with gain and losses rather than established electro-optical non-absorbing systems for telecom operation at 1550 nm: (i) one can combine active (source) and passive (switch-type) functions from the same epitaxial stacks without the need of an expensive epitaxial regrowth step. (ii) the one sided reflectivity while still belonging to reciprocal phenomena, suggests a different effect of external radiation onto a laser, and a potentially larger immunity of optical feedback on lasers, a well-known impairment of lasers that calls, to mitigate it, for the costly addition of garnet-type magneto-optical isolators. In our project, we team two academic labs, C2N and LCF, with the industrial partner III-V Lab, to target a proof-of-concept of InP-based integrated devices that demonstrate both above advantages. One cannot overemphasize the possible importance of the one-sided behavior (the one-sided reflectivity): it should very likely result in the higher immunity of laser linewidth and wavelength to optical feedback from the fiber or optical line, thus leading to the perspective of isolator-free laser diodes in high-performance optical networks, that do not need the usual expensive placement of a garnet-based isolating element to retain their narrow and precise linewidth and frequency and that would remain so under feedback up to -15 dB at least. Laser diodes for telecom are a 2-billion-euros yearly market. Specifically, the project proposes to fabricate two elementary guided-wave devices, – a highly-feedback immune laser diode and a PT-symmetry based switch using laterally coupled waveguides – and next to fabricate their combination on the same active wafer. The wafer itself would be mostly used in gain-and-loss regimes. It would be the first step in a novel architecture for active or passive elements. The proof-of-concept would be also an innovative transfer of a fundamental physics idea to a real-world device. It could be exploited in other domains where electro-optical tuning of the refractive index real part is not a satisfying solution, namely in plasmonics and with glass- or silica-based photonics (it is noteworthy that metals and glass are poor in terms of electro-optical performance). The PARTISYMO project has a duration of 3.5 years, taking into account the impact of the move of C2N lab (former LPN+IEF) to its new building at the heart of the Université Paris-Saclay main campus, scheduled in September 2018, very carefully.

Recently, there has been impressive progress in the field of artificial intelligence. A striking example is Alphago, an algorithm developed by Google, that defeated the world champion Lee Sedol at the game of Go. However, in terms of power consumption, the brain remains the absolute winner, by four orders of magnitudes. Indeed, today, brain inspired algorithms are running on our current sequential computers, which have a very different architecture than the brain. If we want to build smart chips capable of cognitive tasks with a low power consumption, we need to fabricate on silicon huge parallel networks of artificial synapses and neurons, bringing memory close to processing. The Bio-Ice project aims to deliver a new breed of bio-inspired magnetic devices for pattern recognition. Their functionality is based on the magnetic reversal properties of an artificial spin ice in a Kagome geometry. The local control of the magnetic properties gives to our device a learning ability. A consortium with complementary skills (materials science, measurements, characterization and theory) will drive this project having multiple applications.

OBIWAM is a collaborative research-enterprise (PRCE) project composed by three industrial partners and two academic ones, which is voluntarily focused on applications. It aims to design and experimentally demonstrate a real-time-high-resolution microwave imagery system for security applications (body scanners, vision through walls, target detection in opaque environments, non-destructive testing of luggage) using microwave frequencies and photonic and optoelectronic devices. The proposed system relies on a new technique that consists in measuring a single signal by performing an analog coding of the signals received by an antenna network on a single output channel guaranteeing a simplified architecture requiring only a single Analog-to-Digital Converter. The signals collected at each antenna will be optically processed (delays management) and then concentrated to the single output channel by means of a microwave photonics summation. The electro-optical conversion will be carried out using Silicon Photonic modulators, a technology that has a bright future and will ensure the compactness and the low cost of the system. Thanks to a judicious choice of optical delays, the waveforms received by each antenna will be reconstructed in post-processing by applying SIMO or MIMO imaging algorithms. So, for OBIWAM there is a need to include innovative components such as silicon modulators and microwave photonics summation devices, one of the key elements of the system, and new digital signal processing. The aim of the partners is to provide at the end of the project an innovative microwave photonics realtime demonstrator with single-shot/single-channel acquisition and for the detection of targets. It will aim to show the potential offered by an innovative approach and to extrapolate the studies, through simulation, to a system with better image resolution. The development of a system simulation platform that includes both component models and signal processing is thus another challenge of OBIWAM.