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Functional Materials based on their electronic

A ELECTRONIC STRUCTURE-BASED FUNCTIONAL MATERIALS

A1 Diamond & carbon-based nano-structures

A2 Inorganic Nano-materials

A3 Functionalization & nano-structuration of surfaces

A4 Photonic devices

The " diamond and carbon-based nanostructures " sub-axis gather researchers who elaborate diamond -material with a high added value- at different scale (macro, micro or nanocrystalline) together with scientists who finely analyze carbon nano-structures (CNTs, graphene,..) or who study OLEDs. The electronic properties of carbon structures are studied in detail. Applications concern photonic devices, electronics including power electronics and molecular electronics, detectors, etc. The rationale for the carbon-based nano-structures and diamond is that they can be elaborated with the adapted purity and structusre. Other challenges are to be able to produce them in large scale and to make them amenable to a vast variety of chemical, electrochemical and physical treatments prior to their use as components in high-tech devices.

lspm, in collaboration with ITODYS, LPL, MPQ and the Ile de France diamond-network, will focus on overcoming the scientific and technological bottelnecks that are still preventing diamond from playing a central role in the field of electronics (especially power-electronics), in opto-electronics and photonics. These efforts will include:

inhibiting dislocation propagation in bulk diamond using new methods involving etching treatments or thin film deposition (ELOG in particular) fabricating diamond active/passive multi-layers (p, p+, n, intrinsic) (collaboration with GEMaC for n-doped layers) depositing thin or ultra-thin films functionalised or nanostructured for sensor applications (DNA sensing for example) fabricating color centres networks for quantum cryptography (in collaboration with ENS Cachan-Thales, and in the future MPQ) or photonic structures for OLED and organic lasers (collaboration between LPL and LSPM) developing more and more efficient plasma reactors to contribute to the development of a real diamond industrial sector in France. Besides crystal growth, the project will include the development of new processes required to obtain either low dislocation structures or devices that can match the specifications. The teams, involved in diamond growth, diamond doping, its characterisation, functionalisation or (nano) structuration, or even plasma reactors design and laser diagnostics, will consolidate

their facilities in terms of reactors, diamond processing, modelling and growth. New collaborations will be developped between the Labex partners for plasma diagnostics (QCL spectroscopy, LSPM/MPQ) and for diamond functionalization (LSPM/ITODYS), and historical collaborations with complementary teams in the Paris region (GEMaC, ENS Cachan, CEA), in France (LAAS, IN), and international (Warwick in particular, GIA, ...) will be pursued or even reinforced. Organic / inorganic nanostructures : Oleds and organic lasers The LPL group in collaboration with LSPM will be concerned on controlling OLED color and achieving high Q microcavity. It will play on the thickness and the position of the well inside the structure, and it will study the residual absorption of the transparent and conductive electrodes (usually Indium Tin Oxide) used with the OLED heterostructure. Microcavities incorporating very transparent and conductive electrodes with reduced absorption will be developed to push the limits toward higher Q microcavities. New transparent and conductive electrodes obtained by Atomic Layer Deposition will be realized. Another limiting factor for high Q microcavities is the low refractive index of organic materials (typically n=1.7) limiting the reflectivities at the air interfaces at only few percent. Therefore OLEDs embedded in microcavities made with higher refractive index materials may exhibit better quality factors. Beyond oxyde nano-balls, one other possible candidate is diamond. With a good transparency and refractive index n=2.45, the nanostructured diamond can exhibit photonic band gap properties and thus photonic crystal microcavities with high Q

factors can be fabricated. On top of the high Q photonic crystal defect cavities, diamond can be p-doped which makes it a potential candidate for OLED anode thanks to its good transparency and controllable conductivity. These microcavities will be made at LSPM. Carbon nanostructures CNTs. Based on the deep understanding of the local spectroscopy of carbon nanotubes MPQ Lab will study the functionalization and doping of CNTs by STM in order to reveal their influence on the electronic structure of CNTs. In collaboration with LSPM that is able to produce pure or functionalized CNTs or BN and BCN nanotubes, the local electronic structure of these tubes and the effect of their functionalization down to the atomic scale will be studied. Using local spectroscopy, a large range of carbon based model systems for molecular electronics can be investigated. Diamond crystals will be studied by STM as well thanks to a new collaboration between MPQ and LSPM. These local STM studies will be completed by transport measurements.

is a simple test molecule before more complex molecules will be used after synthesis at ITODYS. C60 molecules will be deposited in situ at 4 K inside a nanogap after the electromigration process in order to investigate how the experimental signatures of quantum transport are modified in presence of a molecule and how the molecular levels interact with the electronic and spin degrees of freedom in the electrodes. Graphene. The main topic of this research will be the observation of spin and charge collective excitations in graphene in the quantum Hall effect regime and the study of the resonant coupling between vibrational and electronic degrees of freedom of the graphene layer using an optical tool inelastic light scattering, also known as Raman scattering. The experimental set-up developed at MPQ (SQUAP team) will be based on a split-coil magnet specially designed for optical studies and capable of reaching magnetic fields of 10T and temperatures as low as 1.5K. If successful it may pave the way to future Raman studies of electronic properties of other promising two-dimensional crystals like chalcogenides.

Due to their extremely small dimensions and their related chemical (specific area, reactivity...) physical (magnetic relaxation, quantum confinement...) properties, electronic-structure based functional nanomaterials are the basis of newly emerging nanotechnologies for various device applications and are also at the origin of very fruitful fundamental research. The capabilities for the design, fabrication and study of nanoscale materials, with an emphasis on atomic-level tailoring to achieve desired properties and functions around their electronic structure, are highly exciting challenges.

The sub-axis "inorganic nanomaterials" of the SEAM labex concerns a variety of materials, namely oxydes, semiconductors, metals, which are studied at the nanoscale from 1 nm to 100 nm. The objectives are to make a link between the structure of the

nanomaterials (ultra-thin layers, quantum boxes, nanoparticles) and their physical properties (electronic, magnetic and optical), including also superconductivity, photonics, multiferroïcity. The ultimate goal is to elaborate new devices from these new functionalities. For information storage and telecommunications applications, the SEAM teams (MPQ, ITODYS, MSC, and LSPM will study of the magnetic properties of nanomagnets with a special emphasis on the interplay between intrinsic properties arising from their finite size and collective effects due to the different kinds of interactions between them.

Their objectives are first to produce original nanostructures by chemical or physical routes as powders, thin films supported nanodots, magnetically contrasted nanocomposites or metamaterials, hybrid architectures obtained by controlled aggregation of magnetic nanoparticles, nanostructured bulk metals and ceramics obtained by spark plasma sintering. They also aim at measuring the magnetic properties of these new materials, both in the low frequency (a few Hz) and very high frequency (up to 20 GHz) regimes. Low frequency hysteresis cycles or dynamical susceptibilities are determined by either SQUID or magneto-optical measurements. The goal is to extract key quantities like the magnetic anisotropy for original nanomagnets and to understand the

mechanisms of thermal reversal which is a scientific bottleneck (superparamagnetic limit) in the storage industry. Recent results show that the low frequency reversal is strongly influenced by the high frequency spin-wave modes inside the nanomaterials. For biomedical applications, the project is based on the ITODYS and MPQ skills in magnetic nanoparticles synthesis, their surface coating make them

biocompatible, specific (targeting) and/or sensitive (to pH, temperature, pressure, ionic strength, light, electrical signal, magnetic field, or specific biomolecular interactions ...)and the study of their magnetic and magneto-mechanic behavior under in vivo operating conditions. The ultimate goal is to propose biogenic smart multifunctional nano-tools able to perform, at the same time, several tasks from detection to therapy. These nano-tools can be magnetic hydrogels, vesicles, or just simple hybrid nanoparticles, which will therefore be capable of performing several biomedical tasks in a living body and possess biological functionalities devoted to biochemical/biological recognition. The large available facilities offered by the SEAM Labex are also a token of high level research in such a topic.

Multiferroic nanomaterials
Most materials still display relatively weak coupling between electric and magnetic order which can be a drawback for the development of multiferroic based devices. From a more fundamental point of view the current understanding of the magneto-electrical coupling is still sketchy at best. The SEAM teams (ITODYS, MPQ, LSPM) plan to adopt two strategies, an intrinsic approach based on the elaboration and the study of pseudo single crystals (epitaxial thin films) and an extrinsic one based on the preparation of granular nanocomposites by the integration of magnetic nanoparticles inside a ferroelectric polymer or the fabrication of ultra-thin heteronanostructures using Chemical Vapor Deposition (CVD), Atomic Layer Deposition (ALD), or physical vapor deposition (PVD) films growth techniques and the study of the order coupling. In parallel, the involved teams aim at developing new nanoscale probes such as non-standard near-field microscopy and microstripes-ferromagnetic resonance (FMR) techniques which will allow the study of local magnetization/polarization distribution in the ferromagnetic/ferroelectric nano-systems under the application of magnetic/electric field. Analyzing the near-field microscopy images and the detected electric signal, we'll study the dynamics of the ferroelectric and ferromagnetic domains and hysteresis loops of these domains, at the nanoscale level, under the application of a magnetic/electric field. An exciting prospect (magnonics) in the field of spintronics is to use the wave like excitations of

a magnetic material as a means of transmitting and processing information. Like spintronics, the key goal of magnonics is to read/write non-volatile spin information with minimal or no energy consumption. With wavelengths much shorter than EM waves, spin waves are suitable for the miniaturization of fast devices operating from gigahertz to terahertz frequencies. Hence, magnonic devices can be combined with microwave electronics and photonics technologies. Multiferroic materials could lead to electrical control of magnetic effects and vice-versa. Photonic nano-materials Photosensitive oxide-based nano-materials. New modern applications in the field of photonics (reversible 2D/3D laser microstructuri photovoltaic, etc.) and photocatalysis (depollution, bio-synthesis, etc.) require novel functional inorganic materials with unprecedented high performance and energetic efficiency. These are mainly oxide based nanostructures, often produced by sol-gel and/or RF spray plasma methods. Studies on the elaboration process in close relation with the material electronic structure and related properties are seldom. The goal of NINO-LSPM team is to prepare monodisperse, single phase, highly crystalline and pure photosensitive nanostructured oxides (TiO2, ZnO...) and oxide-based composites fabrication. The process selectivity and kinetics in non-equilibrium condition to control the morphology at the nanoscale will be studied thanks to measurements of the nucleation-growth-aggregation, surface exchange, fluids dynamics, micromixing. With both experimental and theoretical approaches, the coupling between transport phenomena, chemical

reactivity and growth of solid structures will be considered. These studies are tightly connected with the studies of the materials electronic and related optical properties, as well as phenomena of light interaction with the materials, in a collaboration with LPL. Metallic based nanostructures. These nanostructures can be produced by self organized single crystal colloids, lithography or PVD growth on surfaces. Using single crystal colloid articles ultra-high enhancement factors are expected. Accurate positioning of the particles must be dramatically improved over substrates obtained by random deposition of the single-crystal particles to guarantee the reproducibility of the desired optical properties. ITODYS and MPQ research teams will work together to combine colloidal assembly techniques with positioning capabilities of electron-beam lithography to design reproducible and efficient plasmonic substrates for biosensing and molecular recognition applications. The influence of the morphology on th plasmonic response will be studied. To act on the metal nanocrystals morphology, PVD-producing core-shell nanodots can be used. Several systems are nowadays under investigation like Cu@Ag, CuO@Ag, Fe@Au, Fe3O4@Au...

Research on the functionalization and nanostructuration of various surfaces has been speeding up these past five years for the development of new sensors and biosensors and original molecular electronic devices. These domains are currently under study at ITODYS, together with LSPM, MSC, MPQ and LPL.

Sensors and biosensors
CNTs based hybrids, ie. CNTS coupled to organometallic groups such as metallophthalocyanines, exhibit electrocatalytic activity toward several electrochemical reactions and anchored to a surface will be studied to developed new and efficient electrodes. Electrochemically prepared polymers mixed or not to metal nanoparticules or metallic complexes graffed on a surface may form also very sensitive electrodes. DNA-based biosensors with direct electrochemical detection have been already developped. The original results based on analyzing the interactions between gene and electroactive probes allows extending this approach to promising biomimetic molecules such as peptido-nucleic acids (PNA), sequence of DNA

(aptamers) to detect chiral molecules and also oligopeptides for detecting proteins, antibodies biochemical markers.
Different strategies for functionalizing electrode surfaces by ultrathin organic layers will be based on electroformed conductive polymers, electrografted aryl groups or oligomers derived from diazonium salts which are nonmanual methods that allow miniaturisation and functionalization over a large scale, from several square centimetres down to nanodomains. Molecular imprinted polymers (MIPs) with specific recognition nanocavities may act as artificial antibodies and exhibit high selectivity toward the imprinted molecules (organic compounds, bioorganic molecules, metal ions). New methodologies for enhancing mass-transfer through the elaboration of thin films covalently grafted onto an electrode or 3D hierarchical macroporous structures and sensitivity by coupling MIP elements to voltammetric tranducers or to photonic crystals will be developed with the goal to design nanometer-sized hybrid inorganic nanosupport/MIP systems. Diamond is also a material of choice for sensors. Boron doped diamond as well as hydrogenated diamond surface modifiy the electrical conductivity of diamond making it suitable for conception of new sensing devices. Functionalization of diamond layers by photochemically or sonochemically assisted grafting of phenyldiazonium or double functionalized silanes for further immobilisation of biomolecules (enzymes, for example), and control of the diamond/metal interface for implementing ohmic contacts will be an important focus.

These approaches will be investigated in collaboration between ITODYS, LSPM, LPL, MSC and MPQ. Molecular electronics Molecular transport at the nanometer scale has shed new light on many body phenomena in condensed matter (molecular domains at 2D (monolayers), 2D (monolayers), 1D (wire), or 0D (dots)). This approach at various dimensions allows the full understanding of the effect of reduction of size on molecular transport. This needs a tight collaboration between physicists of electronic transport under tip (STM at MPQ) or not (TELEM team at MPQ) and chemists (ITODYS) specialists of electroactive/materials tailored for their grafting and self-assembling capacities onto surfaces. We will fabricate junctions between one molecule and two metallic contacts and investigate how the experimental signatures of quantum transport are modified when a single molecule is inserted in a nanogap. We will also elaborate nano-structured networks using templates, self assembling, nanoprinting, and by formation of mesoporous 2D networks from solutions, the filling of the pores being then carried out by electrochemistry, dipping, or vacuum evaporation. Transport measurements adapted to such nanostructures are necessary. Direct transport measurements through single molecules can be performed at very low temperature and under magnetic field either in transistor geometry with nanometer-spaced electrodes fabricated by controlled electromigration of nanowires or by STM (MPQ - ITODYS). Specific phenomena occurring at the nanometre scale level like the Kondo effect in presence of ferromagnetism or the magneto-Coulomb blockade will

be studied. The interaction between between Physicists and Chemists is of particular importance in this field.

The sub axis " photonic devices " develops quantum devices for the emission of photons, the detection, the manipulation and the storage of photons under different regime. It contributes to the fundamental and applied research in the fields of optics, quantum physics, materials science, and semiconductor devices. Another way to functionalise materials is to change their electronic structure by creating artificial composites typically obtained by deposition of nano-metric layers that gives rise to electronic potential well. The ultimate goal is to control position and energy of individual electrons by ascribing into the matter potentials capable to control their position in the three dimensions of

the space. In the case of photonic devices the electronic properties are tailored to efficiently enhance the interaction between light and matter and generate light emitters, detectors and new devices that incorporate quantum mechanical effects not yet exploited by modern technologies. This research on photonic devices will produce a new generation of devices capable to transform electrons into well-defined photons and vice-versa

Quantum cascade lasers in the terahertz and mid-infrared spectral ranges for the generation of frequency combs. The objective of this workpackage is to demonstrate the generation of frequency combs based on actively mode-locked QCLs emitting in the mid-IR and THz spectral ranges. We target a minimum spectral width of 1THz. To obtain this objective, two main challenges will need to be faced. In the mid-IR spectral range there is presently a difficulty in reaching high modulation depths, owing to a strong absorption of the microwave field inside the laser waveguide. Increasing the modulation depth is a crucial step to enable wide spectral emission. We plan to achieve high modulation depths by embedding the QCL active region in new types of waveguides, similar to the microstrip lines routinely used by microwave engineers. Ways to significantly reduce the average doping density inside the active region will also need to be found in order to reduce microwave absorption. In the THz spectral range, the main issue is related to the relatively narrow spectral gain of present QCLs. To increase the gain spectral width we will exploit

the freedom given bandgap engineering in determining by design the energy of the laser transition. For example, active regions composed of multiple stacks emitting at slightly different frequencies will be used to widen the spectral gain. Photon sources for quantum information based on micro- and nano-structured nonlinear materials. The aim is to conceive, fabricate and characterize new sources of quantum light in the telecom range following two complementary approaches. The MPQ laboratory, after the demonstration of several techniques of phase matching in semiconductor waveguides (birefringence, modal) and counter propagating phase matching) has recently demonstrated a microcavity based source of indistinguishable photons. The team now plan to demonstrate the original properties of the two photon state associated to the counter propagating geometry, such as the direct generation of polarization-entangled Bell states, the two-photon state controlled generation via the proper choice of the spatial and spectral pump beam profile, and to study more complex quantum architectures, including the integration of diode lasers and waveguide interferometers for quantum computation. The LUMEN team at LPL laboratory will work at the conception of a new heralded single photon source based on parametric down conversion in a nonlinear photonic crystal (2D PPLN); the team will study and compare the dispersion management and the induced quasi-phase matching performances when using 1D and 2D periodically poled nonlinear crystal and photonic crystals in LiNbO3 to perform parametric down conversion.

A special attention will be devoted to the gain management in optical parametric amplification and oscillation when using a 2D PPLN. The collaboration between the two teams will include 1D and 2D numerical modeling of micro and nanostructured nonlinear material and photon counting techniques in the telecom wavelength. Quantum well detectors for infrared thermal imaging The objective of this project is to optimize infrared detectors operating in photovoltaic mode, called Quantum Cascade Detectors (QCDs). The performance of these devices will be compared to that of Quantum Well Infrared Photodetectors (QWIPs), thanks to the collaboration with Thales Alcatel 3-5 lab, specialized in the characterization of infrared thermal imagers. In order to improve the performance of QCDs, the physics of the transport in quantum cascade structures must be studied and analyzed, both with and without illumination. The objective is to obtain for the first time a complete picture of the transport in a QCD, leading to the optimum design of a focal plane array. Following this design, devices will be produced at Alcatel Thales 3-5 lab (semiconductor growth, and thermal thermal imager array technological processing). Operation at two different wavelengths will be studied: 8 µm (this wavelength is optimum for night vision), and 16 µm (well suited for space borne observation). Operation of QCDs at both wavelengths will be compared to state of the art QWIP detectors. The first thermal image with a Quantum Cascade Detector will be demonstrated. The final objective is the demonstration of a very high performance detector in the long integration time

regime. Quantum devices operating in the regime of light-matter strong coupling This project is headed by Professor Carlo Sirtori that was awarded by the ERC last year. It deals with the conception and realisation of semiconductor quantum devices that exploit the coherent superposition of two distinct states to obtain new functionalities, in particular focu on the realisation of efficient optoelectronic emitters. The rationale behind the project is that the spontaneous emission, in the THz frequency range, is characterized by an extremely long lifetime when compared to non-radiative processes, giving rise to devices with very low quantum efficiency. This issue can be overcome by developing hybrid light-matter systems, already well known in quantum optics, within optoelectronics devices, in which the material excitations are obtained by electrical injection. With this project we aim to extend the field of optoelectronics by introducing some of the concepts of quantum optics and particularly to implement novel optoelectronic emitters operating in the strong coupling regime between an intersubband excitation of a two-dimensional electron gas and a microcavity photonic mode. Few experimental results in this direction have been already obtained. Midinfrared LEDs based on intersubband polaritons, working up to room temperature, have been demonstrated. Moreover, in these devices we have been able also to observe polariton scattering with optical phonon. Finally, in the THz region we achieved the regime of ultra-strong coupling in which the Rabi frequency is comparable to the photon energy. Photosensitive oxides and hybrids

for reversible laser microstructuring and Photovoltaics This work package is devoted to the controlled fabrication of photosensitive metal oxide based (TiO2, ZnO, ZrO2, etc.) organic-inorganic hybrids. We will combine two approaches based on sol-gel chemistry (see section A3), plasma chemistry and laser photochemistry in order to produce, shape and structure the bulk materials. The choice of metal oxide based hybrids is dictated by their particular electronic and related optical properties that pave the way to large-scale applications, such as laser microstructuration, photocatalysis and photovoltaics. La irradiation will be applied at different process stages in order to structure the material shape and the local properties at the nano- and micro-scale. The laser-triggered photocatalytic transformations will be used for surface functionalization. The following applications are: (1) Surface metallization of the nanostructured hybrids will address 3D-periodic conductive nanostructures that work as metamaterials, (2) the functionalization of the interface of 3D-structured hybrids by biomolecules (e.g. peptides) will address the fabrication of functional scaffolds for 3D-guided cell growth, (3) TCO assembling with silicium will address the full plasma approach for the fabrication of advanced solar cells. The proposed approach for elaboration and processing the photosensitive oxides will open new opportunities for the fabrication of advanced nanomaterials with tuneable surface and volumetric properties at the nano- and micro-scale, and to applications in photonics and biomedicine. LSPM and LPL will participate to this project.

Structural materials

B STRUCTURAL MATERIALS Structural materials are consistent with the French national priorities, concerning the transportation systems improvements, energy consumption reduction and environment. This axis will strongly benefit from the Le Bourget Techno-Centre development, the latter being focused on aeronautics. This project will include industrials such as EADS and Eurocopter, able to federate many small companies, the ASTech competitiveness pole, others actors from the economical world (territorial collectivities, Air France Industry, Dassault services,....), and from research and education (University Paris 13, SUPMECA, in the future University Paris Diderot...). Because of more and more demanding performances, structural materials need to be studied under various thermomechanical loading conditions and environments: mechanical, physical and chemical characteristics need to be measured, sometimes simultaneously; the modeling of their coupled properties must be developed; and some efforts should also be put on the control of elaboration or transformation processes. Consequently, all the aspects concerning material science are present, from the elaboration to the evaluation of the life time and recycling processes, through modeling and development of characterization tools. The fact that these complementary steps can be coordinated within a single LABEX and

treated simultaneously is certainly a condition of fast progress. We project to concentrate our efforts on 3 main subjects based on existing competences Microstructure optimization for enhanced mechanical properties This axis mainly developed in lspm will focus on 3 sub-topics: Multi-scale investigation and modelling of the behaviour of materials in plasticity, damage and fracture. The advanced methodologies present mainly in LSPM include original experimental techniques (in situ mechanical testing combined within SEM, large strain mechanical tests and strain field measurements, high resolution X-Ray diffraction and complex modeling procedures (mean field or full field micromechanical modeling, polycrystalline FE methods, damage modeling based on second gradient approaches, microstructural evolutions during recrystallization, .... They can be applied to the study of all heterogeneous materials like metals, composites, ceramics, elastomers, since they allow to take into account the microstructural organization of composing phases. The aim of these researches is to improve the prediction and optimization of behaviour and life time of the investigated materials. The developed models will also be tested and validated on other types of materials, studied in the LABEX, such as thin films developed for their magnetic properties.

Development of nanostructured structural materials, from nanopowders, based on the use and development of a unique transformation plateform present in LSPM, and comprising very

high pressure devices and severe deformation techniques. This unique set will allow to further develop metallic alloys or composites with ultrafine grains with improved coupled properties, or multiphase alloys with exceptional mechanical properties simultaneous ductility and strength), and to develop new crystalline phases, whose properties can be a priori estimated with the models presented above. This part should greatly benefit from the collaboration with other teams of the LABEX involved in elaboration and characterization of nanopowders. Also, the HP Plateform will be used to elaborate other kinds of materials, such as e.g. biomaterial Development of advanced transformation processes and the control of the resulting properties of materials and structures. Based on the methodology developed at LSPM in the field of thermomechanical treatments (around an asymmetrical rolling mill) we plan to re-visit (EADS and ASTech labeled projects) some other metal forming processes such as flowforming, or warm extrusion. These processes, which are considered as ecological alternatives to machining, need to be associated with an extensive study of the produced mechanical and microstructural characteristics at each step of the process to optimize the final properties and to develop an "environmentally friendly design" approach (thickness and weight reduction, ...). Surface treatments, tribology and physico-mechanical examinations for integrity control Although a lot of research projects inside the LABEX are concerned with surface problems (elaboration of thin films, functionalization of surfaces for various applications, ... ), the mechanical properties of these surfaces are rarely examined. LISMMA from SUP-MECA possesses a unique plateform of tribological devices, which allows simulating a wide variety of contact modes and that are used with associated models, to investigate and improve the mechanical properties of surfaces of materials and systems. This platform will be used, in connection with the expertise of ITODYS in functionalization, of LSPM in the physical characterization of thin films, and of

MSC for some " thin " complex systems, to develop 3 main themes : Development of graded materials and nanostructured coatings, in order to optimize the overall mechanical properties of materials or mechanical parts. LSPM will be involved in this axis for the development of new elaboration processes and of associated mechanical models. One of the main application domains for this axis is the aeronautics industry (the main materials being the Ti alloys and/or some composite materials) and this is why EADS is highly interested by this part of the SEAM LABEX project. "Multifunctionnalization" of surfaces, will combine the expertise of the mechanics in term of control of mechanical properties and the expert thermoplastic polymers); this axis can lead to the development and to the validation (through the use of models and mechanical characterization) of new multi-materials or new assembly techniques, which will have some potential applications for ecological constructions; Materials and wetting phenomena. In order to control the elaboration of coatings (and to get uniform or patterned surfaces) from particles, nanoparticles, liquid polymers,.. on solid or flexible substrates, the physical mechanisms active during solidification processes must be thoroughly understood; this is e.g. what is investigated in MSC for the elaboration of glass sheets (Collaboration with Saint-Gobain) with some controlled experiments and development of analytical models. This type of study will be developed for other applications and completed by the characterization of the final tribological and mechanical properties.

Advanced structural materials and coupled properties Finely architectured materials for structural or/and functional applications: based on the existence of high level platforms concerning the elaboration, the transformation, the characterization of various materials, coupled with some expertise in multiscale modelling, it becomes naturally consistent to develop even more widely the design of new multifunctional materials and their validation through modeling; some examples already exist within the LABEX such as the elaboration of ultrahard materials (LSPM), permanent magnets from Co nanowires (ITODYS and MSC), hybrid materials composed of soft components (foams, sprays, polymers) and inorganics components (nanoparticles, polyometallic or alkooxydes, ...) (MSC), multiferroic materials (LSPM), ..... In this field, only the imagination of the researchers can limit the extent of their work; up to now, the efforts are mainly put on the elaboration and modeling steps. By adding some contributions on the characterization side, the LABEX will become more and more convincing in the development of industrial collaborations. Functionalized structural materials. For all these structural materials which are asked to become " smarter ", and to resist to more and more severe environments, it becomes also essential investigating their coupled properties as well as the interaction between a given material and it environment. In the field of multi-scale modelling, some coupled properties (mechanical and thermal, magnetic, electrical,....) have already been successfully predicted in LSPM for a wide variety of materials. Some teams in MSC work on the development of porous materials that present a good capacity of reducing the vibrations or the sounds and that can be incorporated into structural materials for constructions or aeronautic applications. Also, the investigation of the behaviour of materials under severe

environment (corrosion, high temperatures, Hydrogen embrittlement) is already treated in LSPM which both developed original equipments. More recently, LSPM got involved in this research and developed some FE modeling. In the context of a developing aeronautic technocenter in Le Bourget, all skills are thus gathered inside this LABEX to make significant progresses in the development of smart structural materials (with combined properties) and systems (including their surfaces), capable of resisting in extreme environments. LISMMA from SUP-MECA will be associated to a number of researches.

Modeling and characterization

C MODELLING AND CHARACTERIZATION Modelling/simulation The research performed in the field of simulation and modelling by the groups involved in the SEAM Labex deals with a large number of issues related to material sciences and material processing. SEAM-Labex, thanks to all its Labs, has a large scale expertise that extends from quantum physics to continuum mechanics and physical metallurgy. The research objectives cover a large spectrum that goes from the understanding of the phenomena that govern the physical and chemical characteristics of materials at the nano and sub-nanoscale levels up to the simulation of the macroscopic behaviour and elaboration processes for materials that are dedicated to several kind of applications. The strong, consistent, multidisciplinary and large expertise spectrum allows addressing almost all the issues that are encountered when working on material design, investigation and elaboration.

Researchers are indeed able to design functionalities and nanostructures, to design elaboration processes for materials and to conduct studies to predict the behaviour and the evolution of these materials when used in applications They can also investigate intermediate scales in order to predict how microscopic characteristics, elementary phenomena or collective behaviour of microscopic constitutive elements can affect the behaviour of materials at the macroscopic scale. The research activity performed at lspm on the modelling and simulation of material elaboration processes will be associated with great benefit to the theoretical and numerical investigations performed at LSPM, MPQ, MSC and ITODYS so as to quantitatively take into account the functional and structural constraints when developing developing the material elaboration process

process. Similarly, the models developed on fluid surface interaction will be combined to the models describing structural materials developed at LSPM in order to investigate the chemical, physical and structural changes of materials as well as the consequences of such changes on the behaviour of the materials when used under specific conditions related to targeted applications. Instrumentation The strategy of the SEAM Labex in developing and studying advanced materials is based on the expertise of the partners in growth, structural characterization (TEM and X-ray diffraction), optics and electronics characterizations, surface functionalization, nanostructuration and devices designing, multi-scale modeling and spectroscopy techniques for the study of material transformation processes. Several experimental platforms are available for the Labex researchers, the partners where the main experimental setups are located are indicated for each platform. These platforms are (briefly) : Process for developing materials (elaboration, transformation, functionalization): plasma reactors, soft chemistry, thin films, nano-structuration and self-organization - LSPM, MPQ, ITODYS; Chemical transformation, analysis and characterization of materials - ITODYS; Structural characterization of materials - MPQ, ITODYS, LSPM; Electronics, optics and photonics characterizations - LPL, MPQ, ITODYS, LSPM; Coherent light sources : LPL, MPQ; in situ structural and mechanical properties characterization : alloys, hybrid materials, compacted nanopowders - LSPM; Clean room facilities of U.Paris-Diderot and U.Paris13.

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