PhD subjects
| 53 sujets IRAMIS |
Dernière mise à jour :
Novel concepts for inelastic neutron scattering experiments on a compact source
SL-DRF-23-0435
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Starting date : 01-10-2023
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Personal web page : https://www-llb.cea.fr/Pisp/sylvain.petit/
Laboratory link : https://iramis.cea.fr/llb/NFMQ/
More : https://iramis.cea.fr/llb/Phocea/Vie_des_labos/Ast/ast_sstechnique.php?id_ast=2755
Hemoglobin polymerization and diffusion in different hemoglobin mixtures HbYxHbS(1-x) with Y=At, A0, F…
SL-DRF-23-0418
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=longevil
Laboratory link : https://iramis.cea.fr/llb/MMB/
Pharmacological treatments for sickle cell anemia include hydroxyurea, a molecule that promotes the synthesis of fetal hemoglobin (HbF) which leads to a mixture of hemoglobin HbFxHbS(1-x) in the blood, with HbF partially inhibiting polymerization of HbS. Gene therapy is also used for the treatment of this disease by stimulating the production of therapeutic hemoglobin (HbAt), or normal hemoglobin (HbA0). In collaboration with the Department of Genetic Diseases of the Red Blood Cell at Henri-Mondor hospital, we propose to study the effect of the addition of different types of hemoglobin on the polymerization process as well as the kinetics of oxygen capture at RBC level. This model study is directly linked to the treatments developed to cure this disease and aim to try to better understand them from a molecular point of view.This topic is developed in cooperation with Technical University of Munich.
Parahydrogen hyperpolarization and liquid-liquid extraction for more sensitive and resolved NMR
SL-DRF-23-0732
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Starting date : 01-09-2023
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Personal web page : https://iramis.cea.fr/Pisp/gaspard.huber/
Laboratory link : https://iramis.cea.fr/nimbe/lsdrm/
Generalized Angular Momentum in Attosecond physics: theoretical and experimental studies
SL-DRF-23-0393
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Starting date : 01-09-2023
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Personal web page : https://iramis.cea.fr/LIDYL/Pisp/thierry.ruchon/
Laboratory link : https://iramis.cea.fr/LIDYL/ATTO/
More : https://iramis.cea.fr/LIDYL/
During this PhD project, we will develop specific setups to allow these attosecond pulse to carry angular momenta, may it be spin, orbital or generalized angular momenta. This will open new applications roads through the observations of currently ignored spectroscopic signatures. However, we will set the focus on the fundamental aspects of light-matter interaction in the highly nonlinear regime with angular momenta involved, in particular on beams with unusual topologies such as Möbius strips.
The student will acquire practical knowledge about lasers, in particular femtosecond lasers, and hands on spectrometric techniques of charged particles. He/she will also study strong field physical processes which form the basis for high harmonic generation. He/she will become an expert in attosecond physics. The acquisition of analysis skills, computer controlled experiments skills will be encouraged although not required.
Detailed subject at the web page: http://iramis.cea.fr/LIDYL/Pisp/thierry.ruchon/
In situ and real time characterization of nanomaterials by plasma spectroscopy
SL-DRF-23-0402
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=mbriant
Laboratory link : https://iramis.cea.fr/nimbe/ledna/
Preliminary experiments conducted at LEDNA have shown the feasibility of such a project and in particular the acquisition of a LIBS spectrum of a single nanoparticle. Nevertheless, the experimental device must be developed and improved in order to obtain a better signal to noise ratio, to increase the detection limit, to take into account the different effects on the spectrum (effect of nanoparticle size, complex composition or structure), to automatically identify and quantify the elements present.
In parallel, other information can be sought (via other optical techniques) such as the density of nanoparticles, the size or shape distribution.
Structure-property relationship in graphene nanoparticles
SL-DRF-23-0002
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Starting date : 01-10-2023
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Personal web page : http://iramis.cea.fr/Pisp/stephane.campidelli/
Laboratory link : http://iramis.cea.fr/nimbe/licsen/
For many applications, one should be able to modify and control precisely the electronic properties of graphene. In this context, we propose to synthesize chemically graphene nanoparticles and study their absorption and photoluminescence properties. This project will be developed in collaboration with Physicists so the candidate will work in a multidisciplinary environment.
Porphyrin-based nanostructures
SL-DRF-23-0001
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Starting date : 01-10-2023
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Personal web page : http://iramis.cea.fr/Pisp/stephane.campidelli/
Laboratory link : http://iramis.cea.fr/nimbe/licsen/
In this project, the porphyrins will be studied in collaboration with several groups of Physicists in order to fabricate 1D or 2D covalent networks on surface via the "bottom-up" approach and to study their electronic and optical properties.
Utilization of gases from CO2 for the synthesis of high added value products
SL-DRF-23-0324
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Starting date : 01-10-2023
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Personal web page : http://iramis.cea.fr/nimbe/Phocea/Membres/Annuaire/index.php?uid=enicolas
Laboratory link : http://iramis.cea.fr/nimbe/lcmce/
More : https://iramis.cea.fr/Pisp/thibault.cantat/
We propose in this thesis project to design new catalysts for the synthesis of alkylamines by Fisher-Tropsch reaction on amines, using syngas from renewable sources. The PhD student will search for new catalysts, optimize them, testing them in the Fisher-Tropsch reaction on amines. The objective will be to have a catalyst that is efficient, selective, and not very sensitive to contaminants such as O2 or H2O. Once this system is optimized, the catalyst will be tested in devices to be designed and built, allowing the use of real syngas supplied by other groups at CEA, formed by gasification of biomass for example.
Search for hidden magnetic textures in high-Tc superconducting cuprates
SL-DRF-23-0111
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=dbounoua
Laboratory link : https://www-llb.cea.fr/NFMQ/
More : https://www-llb.cea.fr/
Recently, we discovered that such a state could also lead to the formation of a new type of magnetic correlations within the CuO2 planes. The combination of both kinds of magnetism yields a magnetic texture that may play a crucial role in the PG physics and that has remained hidden to experimental probes up to now. These new magnetic correlations highlight another piece of the high-Tc superconductivity puzzle paving the way towards new investigations.
We propose a PhD project at Laboratoire Léon Brillouin in collaboration with Service de Physique de l’Etat Condensé (Saclay), divided into two experimental parts aiming at a systematic study of these novel magnetic correlations. The first part of the work will be devoted to the crystal growth of several cuprates compounds by means of the travelling solvent floating zone technique. The second part will concern the systematic study of the exotic loop current quantum magnetism in the grown single crystals using polarized neutron scattering.
Hydroborane and borohydride synthesis by hydrogenolysis for hydrogen storage
SL-DRF-23-0365
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Pisp/thibault.cantat/Alexis_Mifleur.php
Laboratory link : https://iramis.cea.fr/nimbe/
More : https://iramis.cea.fr/Pisp/thibault.cantat/index.php
We propose in this project to develop new methodologies to generate boron hydrides from hydrogen in order to immobilize the latter in solid materials for energy storage purposes. The transformation of B-X (X:O,Cl) bonds to their B-H equivalents is a real challenge due to the high affinity of boron with oxygen and the high hydricity of the target compounds which make them reactive hydride donors. Similar work has been described at the LCMCE and by other groups for the synthesis of hydrosilanes and relies on transition metal catalysts or boron-based organocatalysts.
This project will allow the PhD student to develop advanced skills in homogeneous catalysis, characterization of molecular complexes, and gas manipulation.
Translated with www.DeepL.com/Translator (free version)
Innovative signle-atom catalysts for hydrogenation and dehydrogenation of CO2 and LOHCs.
SL-DRF-23-0385
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=cgenre
Laboratory link : https://iramis.cea.fr/Pisp/thibault.cantat/index.php
More : https://iramis.cea.fr/nimbe/LCMCE/
The objective of this thesis is twofold. On one hand, it aims at synthesizing and characterizing innovative isolated atom catalysts based on non-noble metals (Ru, Fe, Mn, Co, Cu) capable of catalyzing the reversible hydrogenation of C=O bonds in CO2 and the dehydrogenative coupling of alcohols with water and of alcohols between them. On the other hand, it aims at exploring the possibilities of systems based on alcohol + water/carboxylic acids as LOHC.
The work will consist in synthesizing, characterizing and testing the catalytic activity of different single atom catalysts. The student will be trained in the techniques of synthesis under inert atmosphere, catalysis in pressurized reactors, as well as in the use of various analytical techniques: SEM, HR-TEM, HAADF-TEM, EDX, XPS, XRD
Stability of efficient triple-mesoscopic perovskite solar cells and modules under real outdoor working conditions
SL-DRF-23-0165
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=foswald
Laboratory link : https://iramis.cea.fr/nimbe/licsen/
Outdoor operational conditions are rarely considered and only few reports can be found. All reports show that, as testing time increase, devices suffer both reversible and more importantly irreversible degradations, which potentially are not detected in a constant temperature, constant one-sun irradiance Maximum Power Point (MPP) tracking procedure, confirming the necessity for outdoor testing under real operational conditions.
This thesis relies on : design, fabrication and characterization of devices to be placed on outdoor test bench for testing under operational conditions.
Chemical reactivity of polymer matrices during aging: formation of unintended compounds and implications for plastics recycling
SL-DRF-23-0044
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Starting date : 01-09-2023
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=sdevineau
Laboratory link : https://iramis.cea.fr/nimbe/lions/
Biogaz irradiation system
SL-DRF-23-0585
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Starting date :
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Personal web page : https://iramis.cea.fr/Pisp/marie.geleoc/
Laboratory link : https://iramis.cea.fr/nimbe/lions/
More : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=jrenault
Cellular level characterization of a vector-based anticancer therapy by exploiting 3H-14C dual labeling, single cell capture in microfluidic chips and beta detection
SL-DRF-23-0244
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Starting date : 01-09-2023
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Personal web page : https://iramis.cea.fr/nimbe/Pisp/florent.malloggi/
Laboratory link : https://iramis.cea.fr/nimbe/index.php
More : https://joliot.cea.fr/drf/joliot/recherche/DMTS/SIMOS
Stream processing for data reduction
SL-DRF-23-0351
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Starting date :
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=mthevenin
Laboratory link : https://iramis.cea.fr/
More : https://www.linkedin.com/in/mathieu-thevenin-2275b03/
Development of bioactive intracranial implants: from laboratory to industry
SL-DRF-23-0315
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Starting date : 01-02-2023
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=deniau
Laboratory link : https://iramis.cea.fr/nimbe/licsen/
More : https://lvts.fr/
of modifying the surface of platinum coils (intracranial implants used to treat aneurysms) in order to accelerate aneurysmal healing. This
was demonstrated in vivo by covalent grafting of a polysaccharide, fucoidane, on the surface of the coils.
Objectives of the thesis
The objectives of the thesis project are the following:
1- Optimize the coating of coils allowing a development under GMP (Good Manufacturing Practices) conditions and adapt the method to
an industrial process.
2- To fully characterize the coating in terms of density, thickness and regularity using physicochemical techniques (ATG, DSC, contact
angle, elemental analysis) and optical imaging (biphotonic imaging, scanning electron microscopy, AFM) and spectroscopic techniques
(EDS, XPS).
3- To validate the conditions retained by implantation of the modified coils in a rabbit aneurysmal model.
Partners: UMR NIMBE LICSEN, BALT Company, LVTS Inserm U1148 and XLIM UMR CNRS 7252, CHU Limoges.
Electroactive carbon support for the fabrication of low platinum loading catalysts
SL-DRF-23-0318
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Starting date : 01-10-2022
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Personal web page : https://iramis.cea.fr/Pisp/bruno.jousselme/
Laboratory link : https://iramis.cea.fr/nimbe/licsen/
Detection of a single Rare-Earth-Ion Spin by a Superconducting-Qubit-based Single
SL-DRF-23-0422
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Starting date : 01-09-2023
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Personal web page : https://iramis.cea.fr/Pisp/emmanuel.flurin/
Laboratory link : https://iramis.cea.fr/spec/GQ/
More : https://iramis.cea.fr/spec/Phocea/Vie_des_labos/Ast/ast.php?t=fait_marquant&id_ast=3409
The crystalline defects of materials can be apprehended as naturally trapped ions in an inert crystalline environment. Due to their immobility and their isolation in the crystal lattice, the electronic and nuclear spins of these ions exhibit excellent coherence times, ranging from a few seconds for electrons to a few hours for nuclei. These systems are thus excellent candidates for encoding quantum information. Superconducting circuits constitute one of the most successful technological platforms for quantum computation. Quantum bits are encoded in artificial electromagnetic oscillators, they are easily controllable and integrable. However, their coherence time does not exceed a few hundreds of microseconds and their manufacture lack of reproducibility, this is one of the main barriers toward the development of processors of more than 100 qubits.
The quantronics group, a pioneer of superconducting circuits, is engaged in a long-term research project which aims at interfacing circuits with the electronic and nuclear spin of a unique crystal defect and thus combine the robustness of natural elements with the integrability of artificial circuits. We recently demonstrated for the first time the detection and manipulation of a single electron spin using a transmon superconducting qubit as a single microwave photon detector [1,2,3]. In this experiment, the single spin is carried by an erbium ion in a scheelite crystal exhibiting a record coherence time of three milliseconds. To extend the spin coherence time to the second timescale, its full natural extent, we propose here to develop a superconducting tunable coupler that can couple and decouple the detector from the spin in a few tens of nanoseconds. Based on the new coupler, we propose to detect and manipulate single nuclear spins in the vicinity of the ion for which coherence could reach hours.
Quantum magnetotransport in shaped topological insulator nanowires
SL-DRF-23-0364
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/spec/Pisp/cosimo.gorini/
Laboratory link : https://iramis.cea.fr/spec/GMT/
Soon afterwards we also showed that the geometrical shape of a nanowire can have dramatic consequences on its magnetotransport properties. Crucially, in shaped topological insulator nanowires electrons propagate on a curved surface, and may thus feel effective gravitational effects. Such emerging gravity takes place on scales which are comparable to the characteristic quantum scales of the system, much as in black holes – nanowires can however be built in labs with current technology, black holes not quite.
Among the numerous open questions in this rapidly growing field, two are most relevant for this project: (i) How are Dirac surface states modified in curved space? (ii) Can a quantum transport signature of effective gravitational nature be singled out in a realistic setup? To answer these both analytical and numerical methods (tight-binding simulations) will be employed.
SL-DRF-23-0740
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Starting date : 01-04-2023
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Personal web page : http://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=varluiso
Laboratory link : http://iramis.cea.fr/LLB/MMB/
Ab initio simulation of catalysts for green chemistry
SL-DRF-23-0719
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Pisp/rodolphe.pollet/
Laboratory link : https://iramis.cea.fr/nimbe/lsdrm/
During this thesis, the student will learn how to perform ab initio molecular dynamics simulations coupled with a method which can reconstruct the free-energy landscape of the hydration reaction for different aromatic nitriles in different in silico experimental conditions. He or she will also have to perform quantum chemistry calculations at a level that can describe all the required intra and intermolecular interactions. This theoretical approach has already been successfully used within our team to describe other chemical reactions in aqueous solution and will be applied to the innovative field of green chemistry.
Thermoelectric energy conversion control via coordination chemistry of transition metal redox ions in ionic liquids
SL-DRF-23-0400
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Starting date : 01-10-2022
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Personal web page : https://iramis.cea.fr/Pisp/sawako.nakamae/
Laboratory link : https://iramis.cea.fr/spec/sphynx/
However, due to the low electrical conductivity of liquids, its conversion efficiency was very low, preventing their use in low-temperature waste-heat recovery applications. The outlook of liquid TE generators brightened in the last decade with the development of ionic liquids (ILs). ILs are molten salts that are liquid below 100 °C. Compared to classical liquids, they exhibit many favorable features such as high boiling points, low vapour pressure, high ionic conductivity and low thermal conductivity accompanied by higher Se values. More recently, an experimental study by IJCLab and SPEC revealed that the complexation of transition metal redox couples in ionic liquids can lead to enhancing their Se coefficient by more than a three-fold from -1.6 to -5.7 mV/K, one of the highest values reported in IL-based thermoelectric cells. A clear understanding and the precise control of the speciation of metal ions therefore is a gateway to the rational design of future thermoelectrochemical technology.
Based on these recent findings, we proposes to further study the coordination chemistry of transition metal redox ions in ILs and mixtures. A long-term goal associated to the present project is to demonstrate the application potential of liquid thermoelectrochemical cells based on affordable, abundant and environmentally safe materials for thermal energy harvesting as an energy efficiency tool.
Solid-state batteries based on composite polymer-ceramic electrolytes : multi-scale characterization and understanding of phenomena at interfaces
SL-DRF-23-0607
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Starting date : 01-10-2023
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Personal web page : http://iramis.cea.fr/Pisp/said.yagoubi/
Laboratory link : http://iramis.cea.fr/nimbe/leel/
More : http://iramis.cea.fr/nimbe/lsdrm/
Sodium is more abundant on earth than lithium and therefore attractive in particular for large-scale stationary storage applications. Lithium-ion technology is generally considered as the preferred solution for applications requiring high energy density, while sodium-ion technology is particularly attractive for applications requiring power.
However, liquid electrolyte batteries present environmental risks such as leaks and can occasionally experience safety problems. Faced with the requirements concerning the environment and safety, solid-state batteries based on solid electrolytes can provide an effective solution while meeting battery energy storage needs. The barriers to overcome allowing the development of all-solid-state battery technology consist mainly in the research of new chemically stable solid electrolytes with good electrical, electrochemical and mechanical performance. For this goal, this thesis project aims to develop “ceramic / polymer” composite solid electrolytes with high performance and enhanced safety. Characterizations by electrochemical impedance spectroscopy (EIS) will be carried out in order to understand the cation dynamics (by Li+ or Na+) at the macroscopic scale in composite electrolytes, while the local dynamics will be probed using advanced techniques of Solid state NMR (23Na / 7Li relaxation, 2D NMR, in-situ NMR & operando). Other characterization techniques such as X-ray and neutron diffraction, XPS, chronoamperometry, GITT ... will be implemented for a perfect understanding of the structure of electrolytes as well as aging mechanisms at the electrolyte / electrolyte and electrolyte/electrode interfaces of the all-solid battery.
Key words: composite solid electrolyte, all-solid-state battery, interfaces, multiscale characterization, dynamics of Li + and Na + ions, electrochemical performance, solid-state NMR, X-ray / neutron diffraction.
Optimization of an extreme light source to study QED dominated plasma states and to pursue technological applications
SL-DRF-23-0387
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Pisp/henri.vincenti/
Laboratory link : https://iramis.cea.fr/LIDYL/PHI/
More : https://ecp-warpx.github.io/
Despite these remarkable properties, femtosecond lasers still lack the intensity required to explore new fundamental regimes where the laser-matter or laser-quantum vacuum interaction becomes dominated by strong-field Quantum ElectroDynamic (QED) effects. These QED regimes are found for example around some astrophysical objects such as black holes and neutron stars. Moreover, femtosecond lasers typically have a wavelength of ~ 1 micrometer, but some potential technological applications (e.g., photolithography) require much smaller wavelengths, of the order of ten nanometers.
In order to manipulate the properties of femtosecond lasers and overcome these barriers, we are studying optical devices called "relativistic plasma mirrors", which can convert a laser pulse into X-UV radiation, while considerably boosting its intensity by Doppler effect.
This multi-disciplinary thesis project concerns the optimization of the “plasma mirror” physical system in order to improve the properties of the boosted laser beams and to enable the use of these boosted lasers for the above mentioned applications.
The activity will rely on Particle-In-Cell numerical simulations with the open-source code “WarpX“ on the latest exascale class supercomputers to determine the optimal parameters for the generation of boosted beams. An auxiliary code development activity is foreseen to support the simulation campaigns. The simulations will be essential to guide experiments that will be performed on our 100 TW laser facility, UHI100, with controlled temporal contrast, which is essential for the realization of this type of experiments, and then on PW-class lasers (e.g. Apollon at École Polytechnique or other international facilities).
The PhD student will have the opportunity to be part of a dynamic team with strong national and international collaborations. He/she will also acquire the necessary skills to participate in laser-plasma interaction experiments in international facilities. Finally, he/she will acquire the required skills to contribute to the development of a complex software written in modern C++ and designed to run efficiently on the most powerful supercomputers in the world. The development activity will be carried out in collaboration with the team led by Dr. J.-L. Vay at LBNL (US).
Bibliography:
> A.Myers et al. “Porting WarpX to GPU-accelerated platforms” Parallel Computing, 108, 102833, 2021
> L.Fedeli et al. “Probing Strong-Field QED with Doppler-Boosted Petawatt-Class Lasers” Phys. Rev. Lett. 127, 114801, 2020
> H.Vincenti “Achieving Extreme Light Intensities using Optically Curved Relativistic Plasma Mirrors” Phys. Rev. Lett. 123, 105001, 2019
> H Vincenti et a. “Optical properties of relativistic plasma mirrors” Nat. Comm. 5 : 3403, 2014
Spatio-temporal control of the high order harmonic emission from crystals
SL-DRF-23-0319
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Pisp/willem.boutu/
Laboratory link : https://iramis.cea.fr/LIDYL/DICO/
More : https://iramis.cea.fr/LIDYL/Phocea/Page/index.php?id=103&ref=99
Attosecond spectroscopy of molecules in gas and liquid phase
SL-DRF-23-0366
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Pisp/pascal.salieres/
Laboratory link : http://iramis.cea.fr/LIDYL/
More : http://attolab.fr/
The student will use attosecond laser techniques to study ultrafast dynamics of molecules in liquid and gas phase. Inner level attosecond photoionization will be used to study in real time: scattering/rearrangement/transfer electron dynamics, as well as solvation effects.
Detailed summary :
In recent years, the generation of sub-femtosecond pulses, known as attoseconds (1 as=10-18 s), has made spectacular progress. These ultrashort pulses open new perspectives for the exploration of matter on a timescale that was previously inaccessible. Their generation is based on the strong non-linear interaction of short (~20 femtoseconds) and intense infrared (IR) laser pulses with atomic or molecular gases. This produces high order harmonics of the fundamental frequency, over a wide spectral range (160-10 nm) covering the extreme ultraviolet (XUV). This high-energy radiation is able to ionize molecules by removing inner-layer electrons. In the time domain, this coherent radiation appears as pulses of ~100 attoseconds duration [1].
With these attosecond pulses, it becomes possible to study the fastest dynamics in matter, those associated with electrons, which naturally occur on this timescale. Attosecond spectroscopy thus allows the study of fundamental processes such as photoionization and addresses questions such as : How long does it take to pull an electron out of an atom or molecule? How does the electron cloud rearrange? These questions have become hot topics in the scientific community but have so far been studied in isolated systems, in the gas phase [2,3]. Advanced sampling technologies now allow us to study these electronic dynamics in a solvated medium where the behavior of electrons on these attosecond timescales is unknown. What energy or electron transfers take place in 10-18 second? Can we measure electron scattering effects in a liquid? These questions are a new challenge for our field on the experimental and theoretical level.
The objective of this thesis is first to implement attosecond techniques established in gas phase to the liquid phase. Two complementary detections will be used, photoelectron detection and transient absorption. By combining the information obtained by each technique, we will be able to measure the scattering of the photoelectron after its creation but also the fate of the ionized molecule: rearrangements/electron transfers, solvation effects.
The experimental work will include the development and the implementation of a beamline, installed on the FAB100 laser of the ATTOLab Excellence Equipment, allowing: i) the generation of attosecond radiation; ii) its characterization by quantum interferometry; iii) its use in photoionization and absorption spectroscopy. Theoretical aspects will also be developed. The student will be trained in ultrafast optics, atomic and molecular physics, quantum chemistry, and will acquire a broad mastery of XUV and charged particle spectroscopy techniques. Knowledge in optics, nonlinear optics, atomic and molecular physics is a prerequisite.
The thesis work could lead to experimental campaigns in French and associated European laboratories (Hamburg-DESY).
References :
[1] Y. Mairesse, et al., Science 302, 1540 (2003)
[2] V. Gruson, et al., Science 354, 734 (2016)
[3] A. Autuori, et al., Science Advances 8, eabl7594 (2022)
Semi/Super-conducting Terahertz plasmonics
SL-DRF-23-0455
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Starting date : 01-10-2023
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Personal web page : https://www.polytechnique.edu/annuaire/laplace-yannis
Laboratory link : https://portail.polytechnique.edu/lsi/fr/recherche/nouveaux-etats-electroniques/terax-lab
More : https://www.polytechnique.edu/annuaire/perfetti-luca
Phase separation of polyelectrolytes: fundamental aspects and application to membranes
SL-DRF-23-0742
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Starting date : 01-11-2023
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Personal web page : https://iramis.cea.fr/Pisp/patrick.guenoun/index.html
Laboratory link : https://iramis.cea.fr/nimbe/lions/
Therapeutical lipidic nanoassemblies in a biomimetic medium: transformation, fate and interactions
SL-DRF-23-0369
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/nimbe/Phocea/Pisp/index.php?nom=frederic.gobeaux
Laboratory link : https://iramis.cea.fr/Pisp/lions/index.html
More : https://www.umr-cnrs8612.universite-paris-saclay.fr/presentation_pers.php?nom=lepetre
Thermoelectric energy conversion in ferrolfuids for hybrid solar heat collector
SL-DRF-23-0399
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Contact : |
Starting date : 01-10-2021
| Contact : |
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Personal web page : http://iramis.cea.fr/spec/Phocea/Pisp/index.php?nom=sawako.nakamae
Laboratory link : http://iramis.cea.fr/spec/SPHYNX/
More : https://www.magenta-h2020.eu
At SPHYNX, we explore thermoelectric effects in an entirely different class of materials, namely, complex fluids containing electrically charged nanoparticles that serve as both heat and electricity carriers. Unlike in solid materials, there are several inter-dependent TE effects taking place in liquids, resulting in Se values that are generally an order of magnitude larger that the semiconductor counterparts. Furthermore, these fluids are composed of Earth-abundant raw materials, making them attractive for future TE-materials that are low-cost and environmentally friendly. While the precise origins of high Seebeck coefficients in these fluids are still debated, our recent results indicate the decisive role played by the physico-chemical nature of particle-liquid interface.
The goal of the PhD project is two-fold. First, we will investigate the underlying laws of physics behind the thermoelectric potential and power generation and other associated phenomena in a special type of complex fluids, namely, ferrofluids (magnetic nanofluids). The results will be compared to their thermos-diffusive properties to be obtained through research collaboration actions. Second, the project aims to develop proof-of-concept hybrid solar-collector devices that are capable of co-generating heat and electricity.
The proposed research project is primarily experimental, involving thermos-electrical, thermal and electrochemical measurements; implementation of automated data acquisition system and analysis of the resulting data obtained. The notions of thermodynamics, fluid physics and engineering (device) physics, as well as hands-on knowledge of experimental device manipulation are needed. Basic knowledge of optics and electrochemistry is a plus. For motivated students, numerical simulations using commercial CFD software can also be envisaged.
Creation and use of a model database for the ab initio calculation of optical properties of materials
SL-DRF-23-0443
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Starting date : 01-10-2023
| Contact : |
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Personal web page : https://etsf.polytechnique.fr/People/Lucia
Laboratory link : https://etsf.polytechnique.fr
More : https://portail.polytechnique.edu/lsi/fr/recherche/spectroscopie-theorique
In this thesis, the student will optimise a model and design a connector for the optical properties of low-dimensional materials. She/he will establish the model database that is needed for this application, and complete it with interpolations, for example with machine learning. This will allow extremely frugal calculations of optical properties.
Spin Orbit Torque smart magnetic sensing
SL-DRF-23-0653
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/spec/Phocea/Pisp/index.php?nom=myriam.pannetier-lecoeur
Laboratory link : https://iramis.cea.fr/spec/LNO/
Detailed subject:
The goal of this thesis is to develop tunneling magnetoresistance (TMR) structures using spin orbit torque to electrically manipulate magnetization and pave the way for reconfigurable magnetic sensors.
Magnetic sensors allow to measure both the magnetic field but also associated quantities, such as current or even the position of an object. They are more and more present in technological objects, as well as in the automotive and medical fields.
Spin electronics, whose experimental demonstration was crowned by the Nobel Prize in Physics in 2007 (A. Fert and P. Grünberg), has opened up important avenues of improvement for magnetic sensors thanks to the sensitivity and miniaturization of the basic elements.
However, a current limitation comes from the fact that the sensor is defined at the time of its manufacture and that its characteristics (such as the range, the sensitivity direction...) are thus fixed at the beginning. Thanks to the spin orbit torque (SOT) phenomenon, which consists in applying a magnetic force through a flow of spin-polarized electrons, it is possible to implement in a spintronics element a function of manipulation of some of the magnetic layers, and thus to imagine a sensor which can adapt itself during its use thanks to the reconfiguration of its references.
The thesis project will consist in developing Tunnel Magneto-Resistance (TMR) systems integrating a level of SOT to drive the sensor response, to fabricate the devices, test their performances and apply them in realistic environment for current sensing and magnetometry. This thesis will be part of the ANR-funded STORM project (starting in December 2022), in collaboration with UMPhy Thales and Crivasense Technologies. It will include the deposition of materials, their characterization in terms of SOT performance, then the realization of devices by microfabrication techniques, and magneto-transport measurements to evaluate the response of the sensors.
Local magnetic microscopy by integration of magnetoresistive sensors
SL-DRF-23-0423
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Starting date : 01-10-2023
| Contact : |
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Personal web page : http://iramis.cea.fr/Pisp/aurelie.solignac/
Laboratory link : http://iramis.cea.fr/spec/LNO/
CVD synthesis of tailored nanodiamonds
SL-DRF-23-0347
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Starting date : 01-10-2023
| Contact : |
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=hgirard
Laboratory link : https://iramis.cea.fr/NIMBE/LEDNA/
This PhD aims to develop a bottom-up synthesis based on sacrificial templates (silica beads or fibers) on which nanometric diamond seeds will be attached via electrostatic interactions. Diamond growth will be achieved by an exposure of the seeded templates to a micro-wave assisted CVD plasma (MPCVD). The growth set-up is already in use at CEA NIMBE for diamond core-shells synthesis [4]. Growth parameters will be adjusted to select the size, the shape and the concentration of chemical impurities (nitrogen, boron) in nanodiamonds. After CVD growth, nanoparticles will be collected by dissolution of the templates. Their crystalline structure, morphology and surface chemistry will be characterized at CEA NIMBE by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman, infra-red (FTIR) and photoelectrons (XPS) spectroscopies. An external collaboration will allow an investigation of the diamond crystalline quality and the identification of structural defects in CVD grown nanodiamonds by high-resolution transmission electron microscopy (HR-TEM).
Several kinds of nanodiamonds will be grown : first, intrinsic particles (without intentional doping), then boron doped particles. Both types of particles will be then surface modified to get a colloidal stability in water. Photocatalytic performances will be measured in collaboration with ICPEES (Strasbourg University). This original synthesis method will also permit to create colored centers (nitrogen-vacancy or silicon-vacancy) in nanodiamonds to exploit their optical properties (collaboration to initiate).
Références :
[1] N. Nunn, M. Torelli, G. McGuire, O. Shenderova, Current Opinion in Solid State and Materials Science, 21 (2017) 1-9.
[2] Y. Wu, F. Jelezko, M. Plenio,T. Weil, Angew. Chem. Int. Ed. 55 (2016) 6586–6598.
[3] H. Wang, Y. Cui, Energy Applications 1 (2019) 13-18.
[4] A. Venerosy et al., Diam. Relat. Mater. 89 (2018) 122-131.
Stress corrosion behavior of mesostructured glass by phase separation
SL-DRF-23-0356
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Contact : |
Starting date : 01-10-2023
| Contact : |
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Personal web page : https://iramis.cea.fr/Pisp/cindy.rountree/
Laboratory link : https://iramis.cea.fr/spec/SPHYNX/
More : https://iramis.cea.fr/spec/index.php
The phenomenon of phase separation in glasses leads to a meso-structured material which can improve mechanical properties such as crush resistance. It is also at the origin of glass-ceramics, consisting of microcrystals dispersed in a glass matrix, developed to take advantage of the benefits of both components: ceramics and glasses. They are used, for example in optical thermometry applications, kitchen utensils, dental materials, etc. However, the stress corrosion behavior of this type of material is still poorly understood.
The objective of this project is to study the link between the meso-structure of glass-ceramics and their stress corrosion cracking behavior. Samples will concern as fabricated samples and their phased separated counterparts which will be achieved by varying annealing protocols. The candidate will make use of an existing SCC experimental set-up allowing experiments in well controlled conditions (Figure 1 top). The rate of crack propagation and its variation with applied stress will be measured for each samples to obtain the characteristic stress corrosion resistance curves. In parallel, the composition and meso-structure of the samples will be studied using different techniques: AFM, SEM, Raman, etc. The candidate will also use a state-of-the-art Atomic Force Microscope (AFM) to characterize post-mortem fracture surfaces. These studies will aid in characterizing the size of phase separation and will feed different statistical tools (stochastic modelling, fractal analysis).
This internship will take place in the SPHYNX lab located in the Condensed State Physics Service which is a joint CEA / CNRS unit (UMR 3680 CEA-CNRS). Researchers study condensed matter physics, from the most fundamental physics to industrial applications. The candidate will have the opportunity to use and learn first-hand advanced methods for characterizing materials and their surfaces, from the macroscopic to the nanometric scale. The approaches will be based on experimental platforms and theoretical tools developed in-house. The candidate will have the opportunity to manipulate theoretical and experimental tools used in the field of materials science, mechanics and statistical physics. Finally, the very fundamental and applied character of this research will allow the candidate to find opportunities in the academic world (thesis) and in industry.
Ising garnet hyperkagome networks for enhanced magnetocaloric effect
SL-DRF-23-0333
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Pisp/francoise.damay/
Laboratory link : https://iramis.cea.fr/llb/NFMQ/
The aim of this PhD project is to find new rare-earth garnets with better magnetocaloric performances, by adequate substitutions on the three available cationic sites of the garnet structure. The project originality is the investigation of high-entropy garnet oxides to achieve this goal. The use of neutron scattering techniques will be a key asset to correlate chemical substitutions with changes in magnetic anisotropy and ground states in applied magnetic field, for an in-depth understanding of the key parameters controlling the magneto-caloric effect.
Study of loop currents state in cuprates
SL-DRF-23-0075
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Starting date : 01-09-2023
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Personal web page : https://iramis.cea.fr/Pisp/113/philippe.bourges.html
Laboratory link : https://www-llb.cea.fr/NFMQ/
In order to get a deeper insight in the intrinsic nature of the exotic magnetism, we propose to use polarized resonant X-ray diffraction (RXD) technique. The polarization analysis is a powerful tool as it allows a selective identification of the anapole and quadrupole terms. Indeed, although associated with multipolar orders, loop currents and quadrupoles state imply very distinct electronic distributions and microscopic origins. While a loop current delocalizes on several atoms, a quadrupole is localized on a single atom [3]. In addition to the RXD measurements, polarized neutron diffraction will be use for the study the phase diagram of several copper oxides materials that include high-temperature superconductors (YBa2Cu3O7-d, HgBa2CuO4+d, (Sr,Ca)14Cu24O41,CuO, etc). The RXD experiments will mainly be carried on the I16 beamline of the Diamond Light Source (U.K.) and the ID32, XMaS beamlines at ESRF. The neutron diffraction at Institut Laue Langevin (ILL) Grenoble.
To perform this research program, we propose a PhD program at Laboratoire Léon Brillouin (LLB-Saclay) in close collaboration with the Laboratoire de la Physique du Solide (LPS-Orsay), both localized at the University Paris-Saclay
References
[1] P. Bourges, D. Bounoua, Y. Sidis, C. R. Phys. 22, 1–25 https://doi.org/10.5802/crphys.84 (2021).
[2] C. Varma, Phys. Rev. B 73, 155113 (2006); M. S. Scheurer and S. Sachdev, Phys. Rev. B 98, 235126 (2018). S. Sarkar et al., Phys. Rev. B 100, 214519 (2019).
[3] M. Fechner et al., Phys. Rev. B 93, 174419 (2016); S. W. Lovesey and D. D. Khalyavin, J. Phys. Condens. Matter 29, 215603 (2017).
[4] D. Bounoua et al, accepted in Comms. Phys. (2022), https://arxiv.org/abs/2111.00525
Photoinduced plasmon satellites
SL-DRF-23-0444
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Starting date : 01-10-2023
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Personal web page : https://etsf.polytechnique.fr/People/Matteo
Laboratory link : https://etsf.polytechnique.fr
More : https://portail.polytechnique.edu/lsi/fr
Hafnium Oxide Ferroelectric Films: from fundamental understanding to optimized, low power device integration
SL-DRF-23-0332
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Pisp/nick.barrett/
Laboratory link : https://iramis.cea.fr/SPEC/LENSIS/
More : https://www.lensislab.com/
Thanks to CMOS compatibility and potential for scaling and 3D integration, it is not only a breakthrough with respect to conventional perovskite-based ferroelectric (FE) devices but also a revolution from an application prospective.
Compared to technologies like Flash or resistive or phase changememories, FE memories are intrinsically low power: reversing the electrical polarization which encodes the information is three orders of magnitude more energy efficient than the nearest competitors.
However, increasing the technological maturity requires understanding the influence of dopants and defects on device performance.
We will use advanced operando materials characterization to trace a path for device optimization by fundamental materials engineering.
Oxygen evolution reaction at the interface between a semiconducting metal oxides and aqueous electrolyte during solar water splitting reaction
SL-DRF-23-0751
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Pisp/dana.stanescu/
Laboratory link : https://iramis.cea.fr/spec/Phocea/Vie_des_labos/Ast/ast_visu.php?id_ast=2977
Orbital/Charge interconversion in 2D electron gazes
SL-DRF-23-0411
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Starting date : 01-09-2023
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Personal web page : https://iramis.cea.fr/Pisp/michel.viret/
Laboratory link : https://iramis.cea.fr/SPEC/LNO/
Influence of a nano-antenna on the intersystem crossing rate of a single molecule
SL-DRF-23-0438
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Pisp/simon.vassant/
Laboratory link : https://iramis.cea.fr/spec/LEPO/
Simulating and imaging nanostructured magneto-electric chiral antiferromagnets
SL-DRF-23-0419
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Starting date : 01-09-2023
| Contact : |
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=jchaulea
Laboratory link : https://iramis.cea.fr/SPEC/LNO/
From Theoretical Spectroscopy to Materials Properties
SL-DRF-23-0447
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Contact : |
Starting date : 01-10-2023
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Personal web page : https://etsf.polytechnique.fr/People/Francesco
Laboratory link : https://etsf.polytechnique.fr
Controlling phase separation in active systems
SL-DRF-23-0341
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Starting date : 01-09-2023
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=cnardini
Laboratory link : https://iramis.cea.fr/SPEC/SPHYNX/
More : https://scholar.google.com/citations?user=F5AitakAAAAJ&hl=en
Future applications may encompass the engineering self-assembling materials using active units, considered as a defining agenda in the community. Furthermore, active systems have theoretically fascinating properties, a fact that drove a very intense research activity lately.
Large assemblies of active units display collective phenomena that are absent in equilibrium. One of the most ubiquitous is phase separation, where even repulsive but active particles phase separate into dense and dilute phases. In some cases, this phenomena resemble to liquid-vapor phase separation of standard fluids. Due to broken time-reversibility, however, active systems can show novel forms of phase separation, comprising a state where the liquid state comprises mesoscopic vapor bubbles (thus resembling to a boiling liquid) or active foams states, where thin liquid filaments are dispersed in the vapor.
Furthermore, in most experimental realization, active systems are `wet’, meaning that particles move in a fluid which itself can mediate interactions among particles, a feature whose consequences are so far little understood theoretically.
The main open theoretical question is how to control these novel states of matter in terms of microscopically tunable parameters. The main goal of this PhD is to fill this gap. This will require both analytical and computational work done on agent based models and continuous descriptions of active systems. If successful, the work will provide a guide for experimentalists to design novel self-assembling materials using active units. Given the ubiquity of phase separation in non-equilibrium contexts, we will further explore the relevance of these results to other out-of-equilibrium systems, such as biological tissues and granular materials.
Many-body physics of topological defects in active materials
SL-DRF-23-0342
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Starting date : 01-09-2023
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=cnardini
Laboratory link : https://iramis.cea.fr/SPEC/SPHYNX
More : https://scholar.google.com/citations?user=F5AitakAAAAJ&hl=en
This PhD project aims at understanding the many-body physics of topological defects in active materials with a combination of analytical and numerical techniques, and at exploring their relevance for collective phenomena in active and living systems.
Investigating the Evolving Chemistry and Crystallography of Sustainable Cements During Their Carbonation
SL-DRF-23-0407
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Starting date : 01-10-2023
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Personal web page : https://www.researchgate.net/profile/Mark-Levenstein-3
Laboratory link : https://iramis.cea.fr/Pisp/lions/index.html
More : https://www.researchgate.net/profile/Stephane-Poyet/
Capture of atmospheric CO2 with nanofluids
SL-DRF-23-0067
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Contact : |
Starting date : 01-10-2021
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Personal web page : http://iramis.cea.fr/Pisp/david.carriere/
Laboratory link : http://iramis.cea.fr/nimbe/lions/
More : https://iramis.cea.fr/Pisp/christophe.fajolles/
In this context, this thesis will study how the addition of nanoparticles improves the recovery of CO2 from liquid amines. These “nanofluids” have proven efficacy, but there is little guidance on how to achieve an appropriate composition, and no consensus on the mechanism that would facilitate the release of CO2 gas.
The objective of this thesis is to propose rational guidelines, which will lead to the best nanoparticle + liquid amine combination, replacing the current trial-and-error approaches. It will therefore be necessary to study how the surface of nanoparticles 1) activates the chemical reaction of release, and 2) facilitates the physical process of nucleation of gas bubbles.
Protection of copper-based heritage metals by sol-gel treatments - understanding the physicochemical mechanisms of corrosion inhibition
SL-DRF-23-0416
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Starting date : 01-10-2023
| Contact : |
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=lmugherl
Laboratory link : https://iramis.cea.fr/nimbe/ledna/
More : https://iramis.cea.fr/nimbe/lapa/
Vertically aligned carbon nanotubes based materials as a novel microporous layer structure for gas diffusion layer in PEMFC
SL-DRF-23-0046
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Starting date : 01-12-2022
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Personal web page : https://iramis.cea.fr/Pisp/mathieu.pinault/
Laboratory link : https://iramis.cea.fr/nimbe/ledna/
layers. The microporous layer is one of the porous layers whose role is to optimize the water distribution. Developing a new micro-porous structure can provide additional information on the parameters influencing water management in the cell and provide a path to improving the fuel cell performance. As part of the PEPR (Priority Research Program and Equipment) H2 PEMFC95 project, the CEA Departments of IRAMIS (Saclay) and Hydrogen for Transport (LITEN-DEHT Grenoble) will collaborate on the development of Optimized and innovative GDLs based on carbon nanotubes, more suitable for the defined operating conditions. Aligned CNT mats have indeed demonstrated their effectiveness as a microporous layer [1]. The performance is at least similar to the best state-of-the-art gas diffusion layer depending on the conditions, and up to 30% improvement in power density could be achieved, without any hydrophobic treatment. For this thesis subject, we propose to continue the development of these diffusion layers integrating CNTs for their interest in terms of stability with respect to oxidation and their hydrophobicity by producing microporous layers with variable porosity. The objective is to substitute them for GDL while improving understanding of its role and, in general, of transport phenomena in a PEMFC core. To do this, the work has two parts. A materials section with manufacturing aspects and characterization of functional properties and an electrochemistry section with fuel cell measurements
Nanodiamond / TiO2 hybrids for green hydrogen production by photocatalysis
SL-DRF-23-0679
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Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/nimbe/Phocea/Membres/Annuaire/index.php?uid=hgirard
Laboratory link : https://iramis.cea.fr/nimbe/ledna/
This PhD aims to elaborate hybrids from ND and TiO2 toward H2 production by photoassisted water splitting under solar-light, following two different strategies: (i) by electrostatic adsorption (layer-by-layer approach) of the different ND and TiO2 materials dispersed in suspension; (ii) by introducing ND during the synthesis of TiO2 nanostructures. Post-synthesis treatments such as annealing in controlled atmospheres will also be considered to favor optimized TiO2/ND interfaces. ND of different crystalline quality (detonation, HPHT milled), shape (rounded, facetted) and size (from 5 to 150 nm) will be prepared with adequate surface chemistries (C-H, C-NH2, sp3/sp2) at CEA by well-established gas-phase annealing methods (under H2, NH3 or vacuum). ICPEES will provide TiO2 nanostructures of different crystalline structure (rutile/anatase), crystalline quality, morphology (nanoparticles, nanotubes) and size using tunable sol-gel and hydrothermal synthesis approach. The effect of surface pre-treatments on TiO2 PC efficiency will be investigated. The various photocatalysts will be characterized all along its development by SEM, HRTEM, XPS, FTIR, XRD, Raman. Then, performances of ND/TiO2 catalytic materials for H2 production by PC will be quantified at ICPEES by means of assessment of photocatalytic water-splitting under solar and visible light irradiation. Kinetics of H2 production will be followed as well as determination of quantum yields will be studied depending as a function of concentration of photocatalyst, nature and concentration of sacrificial agent and light irradiance.
Effect of substitution on ferroelectric and photocatalytic properties of barium titanates nanoparticles
SL-DRF-23-0743
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Contact : |
Starting date : 01-10-2023
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Personal web page : https://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=leconte
Laboratory link : https://iramis.cea.fr/NIMBE/LEEL/
We therefore propose in this subject, carried out in collaboration between the LEEL of the CEA and the SPMS of Centrale – Supelec, to synthesize BaTiO3 nanoparticles by flame spray pyrolysis with substitutions on Ba and O in order to study the effect of these modifications on the ferroelectric properties of the material. The addition of noble metal inclusions on the surface of the particles, likely to improve the catalysis, will also be carried out during the synthesis of the latter. Finally, photocatalysis and piezocatalysis tests will make it possible to establish the links between ferroelectric and catalytic phenomena in this family of materials.
