To find the right proposal !
Internship and thesis proposals
Criteria for selection
Number of proposals
113
1
How tough is yogurt? Local viscoelastic properties of protein gels
Domaines
Condensed matter
Biophysics
Soft matter
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Type of internship
Expérimental Description
Colloidal gels are crucial in biological networks, cell mechanics, food science, and building materials. They result from the aggregation of sub-micron particles such as polysaccharide coils, actin filaments, attractive globular proteins, or cement particles, forming a percolated network that confers solid-like properties under small deformations. In addition, these gels display remarkable nonlinear behavior featuring stress- or strain-stiffening and fractures before irreversible rupture. Recent experiments have shown that the frozen-in stresses that develop during the sol-gel transition strongly impact the nonlinear response of these gels. However, these internal stresses were only evidenced indirectly at the macroscale. Moreover, there is no clear link between the microscale stress heterogeneities inside a colloidal gel and its macroscopic failure time.
The internship, which is part of the MICROFAT ANR project aims to link the frozen-in stresses at the microscopic scale and the gel nonlinear mechanical response at the macroscale. In practice, the candidate will measure the local mechanical properties of colloidal gels composed of proteins using atomic force microscopy and a state-of-the-art nano-indenter (CHIARO by Optics 11) to quantify the frozen-in stresses. Subsequent creep experiments conducted under a confocal microscope will allow the nonlinear gel response to be measured in regions of interest and link the frozen-in stresses with the failure scenario
Contact
Thibaut Divoux
Laboratory : laboratoire de physique, ENS de Lyon - umr 5672
Team : ENS de Lyon, Physique
Team Website
Team : ENS de Lyon, Physique
Team Website
26/03/2024
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Thesis :
Funding :
2
Gelation of binary colloidal mixtures with tunable interactions
Domaines
Condensed matter
Soft matter
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Type of internship
Expérimental Description
Formulated products from the pharmaceutical and food industries are often made up of mixtures of rigid particles, polymers of various architectures, or droplets. These complex systems can gel, i.e., form a percolated network that imparts viscoelastic solid behavior to the material, depending on the total colloid volume fraction and the nature of their physicochemical interactions. Understanding the gelling mechanisms of colloidal mixtures is important for controlling and predicting the rheological properties of many everyday products.
In recent work, we have developed a model binary system involving soft colloids (polyacrylamide microgels, Am) and hard colloids (silica particles), with modular attractive interactions. A series of systems have been studied, successively exhibiting repulsive, attractive colloidal gel behavior and gelling by arrested phase separation by adding either a small amount of a "sticky" co-monomer to the microgels or a co-solvent, such as glycerol.
The aim of this internship is to modulate the attractive interactions of this binary colloidal system via a "solvent" route. The state diagrams will be studied by formulating different mixtures to identify the gelling conditions and the behavior of these binary mixtures under concentrated flow. Next, the reinforcing effects of attractive interactions on rheological properties will be investigated.
Contact
Thibaut Divoux
Laboratory : laboratoire de physique, ENS de Lyon - umr 5672
Team : ENS de Lyon, Physique
Team Website
Team : ENS de Lyon, Physique
Team Website
26/03/2024
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Thesis :
Funding :
3
In search of equal-spin triplet superconductivity: doping MoS2 into the superconducting state
Domaines
Condensed matter
Low dimension physics
Nouveaux états électroniques de la matière corrélée
Topological materials, Quantum Transport, Cavity Quantum Electrodynamics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
In conventional superconductors, Cooper pairs of electrons of opposite spin (i.e. singlet structure) form the ground state. Equal spin triplet pairs (ESTPs), as in superfluid 3He, are of great interest for superconducting spintronics and topological superconductivity. In (few-)monolayer superconducting NbSe2, odd-parity ESTPs have been predicted to arise from the non-colinearity between the out-of-plane Ising spin-orbit field (due to the lack of inversion symmetry in monolayer NbSe2) and an applied in-plane magnetic field. These ESTPs couple to the singlet order parameter at finite field.
We have recently seen preliminary evidence for these ESTPs in tunnel devices at high magnetic fields, in the magnetic field dependence of the superconducting energy gap. More striking spectral features ('mirage gaps') have been predicted for 2H-NbSe2 and TMDs of the same band structure (e.g. MoS2) when the material is doped close to the band edge. In addition to ESTP, recent experimental data on TMDs (including doped MoS2), have been interpreted as evidence for other unconventional superconducting phases, e.g. the finite-momentum ‘orbital FFLO’ state.
The intern will fabricate and measure MoS2 devices with solid state gates. S/he will fabricate contacts with electron-beam lithography and testing TMD contact to them, before proceeding to fabricate gates. S/he is welcome to participate in other work on TMDs going on in the NS2 group at the Laboratoire de Physique des Solides.
Contact
Charis Quay
15/02/2024
/
Thesis :
Funding :
4
Phases et polarisations singulières pour l’interaction quantique laser-atome
Domaines
Quantum optics/Atomic physics/Laser
Quantum information theory and quantum technologies
Non-linear optics
Type of internship
Expérimental et théorique Description
Les techniques actuelles permettent de façonner -à la carte- les lasers en intensité, en phase et en polarisation. Ainsi une phase en hélice produit un vortex optique; celui-ci transporte un moment angulaire orbital (OAM) qui est une grandeur quantique. Le vecteur optique quant à lui, est obtenu en façonnant la polarisation.
Ces singularités de phase ou de polarisation ouvrent vers de nouvelles interactions laser-matière liées au caractère quantique de l’OAM et de la polarisation, et trouvent des applications en quantique. : intrication, spectroscopie, turbulence optique, optique non linéaire, senseurs, etc.
Au LCPMR nos recherches concernent l’interaction de vortex et vecteurs optiques avec des atomes - chauds ou froids- pour créer des paires d’OAMs et les intriquer, pour observer l’évolution des vortex/vecteurs optiques en interaction résonante avec les atomes et pour réaliser des senseurs magnétiques.
Lors du stage l’étudiant se familiarisera avec les SLM (Spatial Light Modulator), créera des singularités et les caractérisera. Il pourra les appliquer à une vapeur de rubidium, placer celle-ci dans un environnement magnétique pour observer la transparence induite. Il pourra évoluer vers l’application à des atomes froids ou le couplage vecteur-vortex qui marie deux grandeurs quantiques du photon.
Le sujet ouvre sur une thèse liée aux aspects fondamentaux de ces lasers singuliers et leur utilisation.
Contact
Laurence Pruvost
04/02/2024
/
Thesis :
Funding :
5
Interaction d’une barre de flot avec la bathymétrie : Etudes expérimentales des mécanismes de diffusion, diffraction, réfraction et absorption de l’onde de marée dans un fleuve.
Domaines
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Metrology
Type of internship
Expérimental et théorique Description
La barre de flot consiste en l’onde de marée qui remonte le cours d’un fleuve en la barrant et ce pendant une phase de marnage (flot) importante. Dans sa forme simple, elle est caractérisée par un front principal et des ondulations secondaires (éteules). Pour des conditions plus rigoureuses, elle devient déferlante. La bathymétrie a une importance cruciale non seulement sur le type de barre de flot mais aussi sur sa vitesse d’avancée : par exemple, des berges inclinées génèrent un jet de rive turbide, le rat noir ou mascaret en gascon ; de même, des variations de profondeur induisent une transition latérale ondulante-déferlante de la barre de flot ; une variation longitudinale de la profondeur comme un banc de sable peut stopper l’onde de marée et ou provoquer une réflexion partielle et des figures d’interférences ou bien alors un îlot central qui vient couper la barre dont chaque partie peut se propager dans des chenaux avec des caractéristiques différentes (pentes, hauts-fonds, vitesses des courants, formes et constitutions des berges…).
Dans ce projet, nous souhaitons explorer l’influence de la bathymétrie sur la propagation de la barre de flot grâce à notre nouvelle méthode de génération de mascaret en laboratoire et qui nous permet de faire des expériences à échelle décamétrique avec des fonds variables comme des bancs de sable ou même une île…
https://germain-rousseaux.cnrs.fr
Contact
Germain Rousseaux
29/01/2024
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Thesis :
Funding :
6
Interaction onde-courant avec application à la Gravitation Analogue
Domaines
Soft matter
Physics of liquids
Relativity/Astrophysics/Cosmology
Fields theory/String theory
Hydrodynamics/Turbulence/Fluid mechanics
Metrology
Type of internship
Expérimental et théorique Description
Suite aux stages du LABEX Interactifs de Poitiers (Rita Nohra (2020 : montage de l’expérience) ; Axel Marzin (2022 : mesure de surface libre par stéréo-réfraction) et Thibault Mergault (2023 : mesure de surface libre par scanner)) sur l’interaction d’ondes de surface avec un ressaut circulaire comme modèle de fontaine blanche analogue, nous souhaitons comparer la figure de diffraction-interférence due à la diffusion d’onde de la fontaine blanche avec celle de son renversé temporel à savoir un trou noir hydraulique. Celui-ci sera modélisé par un siphon avec ou sans rotation spontanée via l’étirement de la vorticité dans l’écoulement.
Dans les deux cas de figures, le travail du stagiaire de M2 sera de nature expérimental et numérique avec l’existence d’une expérience de coin de table avec une pompe et un aquarium permettant de créer des écoulements axi-symétriques et d’un code de calcul de la trajectoire des rayons et des fronts d’ondes (Matlab/Python). Les mesures de surface libres combineront stéréo-réfraction et/ou scanner selon les régimes dynamiques ou statique avec le passage à de la glygérine cette année pour limiter la turbulence et les instabilités observées dans l’eau dans la phase de développement des méthodes optiques de mesure de surface libre lors de 3 précédents stages.
https://germain-rousseaux.cnrs.fr
Contact
Germain Rousseaux
29/01/2024
/
Thesis :
Funding :
7
Electromagnetic simulations for near field GHz spectrometer
Domaines
Condensed matter
Topological materials, Quantum Transport, Cavity Quantum Electrodynamics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Théorique, numérique Description
The advances of circuit quantum electrodynamic (cQED) have enabled tremendous progress
both in the field of quantum computing and quantum sensors. It is now possible with such
circuits to detect accurately single photons in various range of frequencies, potentially
giving access to microscopic excitations in condensed matter systems.
However, the current tools are usually lacking spatiality and sensitivity. In that regard, in the
lab we are pursuing an endeavour to combine cQED methodology [1] with the latest
development in scanning probe techniques[2]. The idea would be to develop a scanning
nano-antenna to get access to single photon processes at the heart of condensed matter
systems with nanometer resolution.
The goal of this internship is to explore numerically different geometries of nano-antennas
and optimize the electromagnetic coupling with its environment at the relevant frequencies.
A first part of the internship will consist in designing and simulating this nano-antenna with
HFSS ANSYS. If time permits, you will be able to start the fabrication process by making
tips and on-chip antennas by state of the art lithography techniques. You will also participate
in the rest of the lab activities and discussion around the project.
The results of this internship will directly impact the design of future nanoantennas. It
requires creativity, rigor and a good understanding of classical electromagnetism.
Contact
Arthur Marguerite
12/01/2024
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Thesis :
Funding :
8
Quantify friction forces in forced wetting on polymer layers
Domaines
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
Polymer layers are adaptative surfaces : their physicochemical properties change during the spreding of a liquid above it. In order to understand the mechanisms of energy dissipation at the contact line, we propose to build a droplet tribometer: the friction forces will be measured down to tens of nanometers. This will pave the road to have a better understanding of the coupling between the hydrodynamics of liquid wetting and the substrate dynamics.
Contact
Marion Grzelka
19/12/2023
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Thesis :
Funding :
9
Wetting dynamics of polymer liquids from the macro to the nanoscale
Domaines
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
The aim of this project is to understand the mechanisms of energy dissipation during spontaneous spreading of a drop on a nanotextured substrate. As part of this internship, the student will study the wetting of nanotextured surfaces by conventional optical microscopy techniques (to probe macroscopic scales) and X-ray reflectivity (to probe nanoscopic scales).
Contact
Marion Grzelka
18/12/2023
/
Thesis :
Funding :
10
Exploring nonlinear phenomena in soft structures
Domaines
Soft matter
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
Context. The laws of linear elasticity rely on the assumption that deformations should remain small. For conventional solids, this is usually true. For soft solids (polymers, rubbers, gels …) however, a moderate stress can induce a significant strain, meaning that nonlinear events are likely to occur.
Objectives. Thanks to optical detection methods, we will track nonlinear phenomena in simple flexible structures [1]. Starting from a soft beam undergoing a parametric forcing, we will look for signatures of instable behaviors [2]. Soft polymers can easily be molded in different shapes which will allow us to explore a variety of configurations. As a possible direction, one could load the elastic structure with iron magnetic particles in order to monitor its mechanical properties with an external magnetic field [3]. This system also provides a new platform to investigate nonlinear wave-wave interaction in the context of elastic fields [4].
Perspectives. Understanding the motion of soft structures is crucial for applications ranging from energy harvesting to soft robot’s actuation. The implementation of a nonlinear self-propelled robot prototype will be considered.
Contact
FRANCOIS PETRELIS
15/12/2023
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Thesis :
Funding :
11
Random surfaces and models of Earthquakes
Domaines
Statistical physics
Soft matter
Nonequilibrium statistical physics
Kinetic theory ; Diffusion ; Long-range interacting systems
Type of internship
Théorique, numérique Description
Recent studies on models of Earthquakes (EQ) have identified a connection between properties of earthquakes and random walks [1].
More precisely, in 1 dimensional models, earthquakes develop along a line and their properties depend on the value of the stress which can be modelled as a random walk. In nature, a 2 dimensional geometry is more pertinent to describe faults where earthquake occurs. The stress as a function of position is then a random surface.
This random surface evolves by the successive modifications due to each earthquake. This amounts to the problem of deposition of objects of varying size (the objects are the analogous of the effect of each event on the stress seen as a random surface).
During this internship, we want to investigate the statistical properties of this random deposition process. How do the surface properties evolve in time ? Is there an statistically stationnary regime at long time ?
This will be achieved by numerical simulations of the process and data analysis of the obtained results.
If the candidate is interested, it is also possible to perform analytical calculations using methods of probability theory. Collaborations or discussions with mathematicians are possible.
Contact
FRANCOIS PETRELIS
09/12/2023
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Thesis :
Funding :
12
Fully-funded Research Internships at Rice University, USA
Domaines
Condensed matter
Low dimension physics
Nouveaux états électroniques de la matière corrélée
Topological materials, Quantum Transport, Cavity Quantum Electrodynamics
Non-equilibrium Statistical Physics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
The Smalley-Curl Institute at Rice University (in Houston, Texas, USA) has fully-funded research internship openings on a variety of projects. The list of the detailed description can be found in the attached PDF. To be considered for financial support, please email Alma Catala Luna (alma.catala@minesparis.psl.eu) , Jean-Francois Allemand (jean-francois.allemand@phys.ens.fr) and Yonglong Xie (yx71@rice.edu) with your CV and a ranked list of the top 3 projects you are interested in. If you have any questions, please email Yonglong Xie (yx71@rice.edu).
Contact
Yonglong Xie
08/12/2023
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Thesis :
Funding :
13
Reconfigurable active matter in 3d
Domaines
Condensed matter
Statistical physics
Soft matter
Physics of liquids
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Type of internship
Expérimental et théorique Description
Active systems exhibit fascinating pattern formation, and collective dynamics not seen in conventional materials. A key consequence of our improving understand of active matter the potential for the application to biological systems, from collective behaviour in fish to insect swarms, such as, as these in general are active due to processing of energy.
Yet to make progress in understanding active matter, simple, controllable and well-characterized systems play a key role and among these are active micron-sized particles (colloids). Here the interactions between the particles are well-understood and machine learning methods facilitate long—standing challenges with coordinate tracking. In particular, colloidal particles assemble in to a variety of structures, which can be interpreted with statistical mechanics. However almost all work with active colloids has used (quasi) 2d systems.
We have developed a 3d active colloidal system of dipolar particles which are active in the xy plane and which have already produced two new phases. This project proposes to investigate further the behaviour of this exotic, and yet well-controlled system. The project may be carried out in experiment, or in computer simulation as we have also developed a simulation model of the same system.
Contact
Paddy Royall
07/12/2023
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Thesis :
Funding :
14
Understanding relaxation in deeply supercooled liquids: a computational approach
Domaines
Condensed matter
Statistical physics
Soft matter
Physics of liquids
Non-equilibrium Statistical Physics
Type of internship
Théorique, numérique Description
Despite decades of intense study, the staggering increase in relaxation time in liquids supercooled below their freezing point (the glass transition), there is still no consensus around the underlying mechanism. In this way, the glass transition is a scientific revolution in the sense of Thomas Kuhn, in that mutually incompatible theories give equally good descriptions of the available data. Computer simulation (and experiments with colloids) promise the ability to resolve this challenge, due to the particle-resolved data which enables analysis not otherwise possible, capable of discriminating between theories. Yet, accessible timescales with both approaches limit the data obtained to a dynamical regime where relaxation is quite well—understood, the so-called mode-coupling regime.
Recently this has begun to change. In particular, supercooling below the mode-coupling crossover has opened the possibility to probe the predictions of dynamic frustration and thermodynamic descriptions across many decades in time [5,6]. This project builds on such recent work and uses computer simulation to address the following outstanding questions: what is the nature of the excitations of dynamic facilitation at very deep supercooling? How do these couple to co-operatively re-arranging regions at larger length- and timescales? And how are excitations related to the dynamical phase transition that underlies the glass transition in the facilitation picture?
Contact
Paddy Royall
07/12/2023
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Thesis :
Funding :
15
Cloud microphysics and global warming
Domaines
Statistical physics
Soft matter
Physics of liquids
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Kinetic theory ; Diffusion ; Long-range interacting systems
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
Autumn 2023 smashed the previous global temperature record. It implies a strong acceleration of global warming, transient or not, for which the most likely explanation is a decrease of human-made aerosols as a result of reductions in China and from ship emissions. The aim of the internship and the PhD thesis is to investigate cloud physics, in connection to global warming issues, using a combination of experimental, theoretical and numerical work, from the nucleation of nanodrops to the organisation of clouds by convective aggregation.
Contact
Bruno Andreotti
20/11/2023
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Thesis :
Funding :
16
Exploring Combined Mathematical Techniques for Precise Computation of Resonance Properties
Domaines
Nuclear physics and Nuclear astrophysics
Type of internship
Théorique, numérique Description
The computation of resonance properties relies on various mathematical techniques, with a particular focus on the width of a state, representing the inverse of its half-life time ℏ. This width significantly influences the scattering amplitude in the proximity of the resonance energy and demands precise prediction. One method, complex scaling (CS), involves rotating momenta towards the complex plane, unveiling poles of the S-matrix. Similar momentum distortions to the complex plane are utilized by several others methods.
However, the use of a complex potential as a meta-model for absorption from the numerous other open channels induces a counteractive rotation of the S-matrix poles. This phenomenon raises the need to explore a combined approach integrating both techniques. The objectives of this internship encompass:
I. Investigating the synergy between complex scaling and complex potential to minimize the required CS rotation for discovering pole locations.
II. Analyzing the trajectory of the poles related to the imaginary component of the potential to understand their behavior.
III. Exploring the mathematical properties of the Jost function in the presence of a complex potential.
The internship aims to refine the computation of resonance properties and deepen our understanding of their mathematical underpinnings.
Contact
Guillaume Hupin
20/11/2023
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Thesis :
Funding :
17
Application of Eigenvalue Continuation method to the continuum.
Domaines
Nuclear physics and Nuclear astrophysics
Type of internship
Théorique, numérique Description
The Eigenvector Continuation (EC) method has emerged as a pivotal technique in nuclear structure analysis, standing as a standard tool for evaluating convergence properties within many-body methods. This method involves parameterizing the Hamiltonian to control its perturbative nature. In conjunction with considerations such as mesh size and other factors, numerical methods yield a finite set of results based on the parametrized input. These results encompass energies and eigenvectors expanded as Taylor series or Padé approximations, with coefficients tailored within a parameter range where the technique attains near-exactness.
A significant parallel exists between the EC workflow and methodologies in machine learning. Similar to the development of an AI algorithm, the EC approach necessitates using a training set to parameterize the algorithm before making predictions in uncharted regions beyond the training data. Despite encountering efficiency challenges in computing states across continua due to high-dimensionality, certain standard scattering techniques enable operations within a finite internal region.
These methodologies facilitate the application of EC to predict converged reaction observables. The primary aim of this project is to investigate the application of EC to a specific scattering solver, with a particular emphasis on integrating it with the No-Core Shell Model possessing continuum capabilities.
Contact
Guillaume Hupin
20/11/2023
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Thesis :
Funding :
18
Magic angle in graphene
Domaines
Condensed matter
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental et théorique Description
Condensed matter physicists used to associate new exotic properties to new materials development. In 2018 a paradigm shift happened with the observation of superconductivity in two layers of graphene with a relative crystallographic rotation of ~ 1.1 degrees, the so-called magic angle twisted bilayer graphene (MATBG). This unprecedented new knob to change properties of 2D materials is already showing a plethora of unexplored properties and leading to a universe of new technological applications in the new and fast growing field of twistronics (Twistronics: control of the electronic properties of 2D materials in a van der Waals heterostructure by changing their relative crystallographic alignment)
The unexpected behavior in MATBG is due to the existence of flat bands in its electronic band structure. These flat bands are the product of the interplay of interlayer tunneling and angle-induced momentum mismatch, which guarantees a large density of states and therefore an amplification of the effects of interactions. This causes correlated states which manifest experimentally by the emergence of new ground states such as superconductivity (SC), Mott insulators and quantum anomalous Hall effect (QAHE). In this internship, the student will fabricate such a device and perform electronic transport measurements (current and shot noise) to reveal its fundamental properties.
Contact
Preden Roulleau
17/11/2023
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Thesis :
Funding :
19
Computer simulations of plasma-based particle accelerators
Domaines
High energy physics
Relativity/Astrophysics/Cosmology
Non-linear optics
Kinetic theory ; Diffusion ; Long-range interacting systems
Type of internship
Théorique, numérique Description
The Accelerator Modeling Program (AMP) is a program within Berkeley Lab that focuses on high-performance computing (HPC) to model advanced particle accelerators, laser-plasma interactions and plasma devices (including fusion devices).
With this project, the intern will have the opportunity to contribute to ongoing research and gain hands-on experience in the field of computational physics within an open and team-science driven environment. Specifically, the intern will use and/or contribute to the development of the Beam, Plasma & Accelerator Simulation Toolkit (BLAST, https://blast.lbl.gov), which includes the code WarpX (https://github.com/ECP-WarpX/WarpX), an open-source massively-parallel Particle-In-Cell code that was awarded the prestigious 2022 ACM Gordon Bell Prize. For a more detailed overview of the group's research, see the following video: https://youtu.be/V_XXXDM_ZTA?t=1
The intern will participate in the advancement of theoretical and computational beam accelerator and plasma physics, through one or more of the various activities that occur in the program, offering a wide range of possibilities:
- Investigating physics through computer simulations to support theoretical and/or experimental studies of plasma-based particle accelerators.
- Improving simulation tools for better performances on supercomputers, or for simulating new physics.
- Exploring novel numerical schemes and algorithms to improve simulations’ reliability.
Contact
Remi Lehe
16/11/2023
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Thesis :
Funding :
20
Analog time reversal processor for radiofrequency signals
Domaines
Quantum optics/Atomic physics/Laser
Quantum information theory and quantum technologies
Type of internship
Expérimental Description
Time reversal is a technique based on the invariance of the wave propagation equation in an inhomogeneous medium. It ensures spatial and temporal refocusing of a wave after having recorded the transmission channel signature. When the propagation medium is non-stationary, the transmission channel characteristics keep changing. The time-reversed signal must be sent as quickly as possible, otherwise the refocusing will not be effective. In the first demonstrations of time-reversal with RF waves, analog-to-digital converters (ADC) were used, limiting the processing bandwidth. In the aim of reaching the GHz regime, the latency time becomes problematic because of the limited sampling rate of ADCs. Conversely, a fully analog solution has the advantage of avoiding this conversion step.
At Institut Langevin, we design original analog architectures for processing optically-carried radiofrequency signals based on light-matter interaction in rare-earth ion-doped crystals. In particular we recently proposed an architecture able to generate controlled, time-reversed copies of arbitrary waveforms. The goal of the internship will be to advance the development of this time-reversal processor, first using arbitrary signals and then using real RF signals reverberated in a cavity.
Contact
Anne Louchet-Chauvet
Laboratory : Institut Langevin - UMR7587
Team : IL: NCIS (New Concepts for Imaging and Sensing)
Team Website
Team : IL: NCIS (New Concepts for Imaging and Sensing)
Team Website
15/11/2023
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Thesis :
Funding :
21
Inertial sensing based on optomechanical coupling in rare-earth-doped crystals
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Quantum information theory and quantum technologies
Metrology
Type of internship
Expérimental Description
The realization of a cryogenic, broadband, high-sensitivity accelerometer is a major challenge in many physics domains, from quantum technologies to seismology and gravitational wave detection. In rare-earth ion-doped crystals, well known for their very narrow optical transitions at low temperatures, and increasingly used in quantum technologies, the energy levels are coupled to the mechanical stress of the host matrix via the crystal field around the ion.
We have recently demonstrated that this coupling can be exploited to provide a continuous optical measurement of the mechanical vibrations of a cryostat, with an already promising sensitivity and bandwidth. This measurement is based on the continuous interrogation of the optical transition with a monochromatic laser.
The internship will consist in pushing the development of this sensor to achieve an ultra-sensitive, unidirectional and calibrated accelerometer.
Contact
Anne Louchet-Chauvet
Laboratory : Institut Langevin - UMR7587
Team : IL: NCIS (New Concepts for Imaging and Sensing)
Team Website
Team : IL: NCIS (New Concepts for Imaging and Sensing)
Team Website
15/11/2023
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Thesis :
Funding :
22
Thermal Hall effect in Bismuth
Domaines
Condensed matter
Nouveaux états électroniques de la matière corrélée
Type of internship
Expérimental Description
See pdf attached.
Contact
Arthur Marguerite
14/11/2023
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Thesis :
Funding :
23
Surface tension vs elasticity gradient
Domaines
Soft matter
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Théorique, numérique Description
In this project, we will conduct Finite Elements Simulations of soft materials with a surface topography, surface stresses, and a gradient of surface elasticity. We will use the software COMSOL, and put emphasis on understanding the effect of elasticity gradient on surface mechanics. The results will be directly compared with existing experimental results
Contact
Nicolas Bain
13/11/2023
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Thesis :
Funding :
24
Deciphering mechanical homeostasis with FEM
Domaines
Biophysics
Soft matter
Physics of living systems
Type of internship
Théorique, numérique Description
In this project, we will conduct Finite Elements Simulations of local contractions inside homogeneous materials, and evaluate how stresses propagate as a function of material properties. We will use the software COMSOL, and put emphasis on understanding the link between material nonlinear properties and stress propagation. The results will be directly compared with ongoing experimental results.
Contact
Nicolas Bain
13/11/2023
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Thesis :
Funding :
25
Antibunching effect and squeezed light in a cold atom ensemble
Domaines
Quantum optics/Atomic physics/Laser
Quantum optics
Non-linear optics
Type of internship
Expérimental Description
Cold atoms coupled to photons are a promising platform for quantum information,
computation and communication. The light radiated by a quantum emitter, such as an atom, generally features quantum correlations and squeezing , which are at the heart of many applications in quantum technologies. While antibunching is the key ingredient for single photon sources, squeezed light is an important tool for sub shot noise quantum sensing.
The goal on our experiment is to detect antibunching and squeezed light with many quantum emitters in a 3D system . This will be implemented and studied on our cold atom experiment, taking advantage of our experience with generating clouds of cold atoms with large optical thickness, a prerequisite for this project. The current collaboration with the group of Arno Rauschenbeutel will finally help to determine the experimental parameters needed to observe this antibunching effect.
Contact
Mathilde Hugbart
10/11/2023
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Thesis :
Funding :
26
Etude théorique et numérique de la transition quantique classique par une approche utilisant les marches aléatoires branchantes.
Domaines
Statistical physics
Non-relativistic quantum field theory, quantum optics, complex quantum systems
Non-equilibrium Statistical Physics
Kinetic theory ; Diffusion ; Long-range interacting systems
Nuclear physics and Nuclear astrophysics
Type of internship
Théorique, numérique Description
Ce stage se propose d'explorer le lien entre l'équation de Schrödinger et la mécanique statistique des processus critiques, d'un point de vue théorique et numérique. Les développements formels -qui peuvent être vus comme l'étude de la quantification stochastique de Nelson dans le secteur non relativiste- s'appuieront sur des travaux relativement récents de Nagasawa et seront interprétés à la lumière de la théorie de l'onde pilote de Bohm. Les aspects numériques seront réalisés par une extension d'algorithmes de type "Diffusion Monte Carlo" du régime stationnaire au régime transitoire. On cherchera en particulier à reproduire numériquement le phénomène de "quantum carpet" avec ces outils, ainsi que la transition quantique/classique.
Contact
Eric Dumonteil
10/11/2023
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Thesis :
Funding :
27
Probabilistic description of chaotic deterministic systems
Domaines
Statistical physics
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Kinetic theory ; Diffusion ; Long-range interacting systems
Type of internship
Théorique, numérique Description
The dynamics of chaotic systems exhibit an extreme sensitivity to initial conditions. Even the slightest variations between initially close trajectories lead to exponential separation over time, rendering long-term predictions exceedingly challenging. A famous example is the long-term motion of the inner planets in the Solar System. Despite the deterministic nature of these systems, their behavior ultimately evolves into a state of actual randomness on long time scales. Consequently, it becomes necessary to establish a statistical description, framed in terms of a probability density defined over the phase space of the dynamics.
In the conventional Monte Carlo approach, the probability density of physical observables is estimated from a large ensemble of numerical integrations of the equations of motion. The internship opportunity presented here aims to explore an alternative approach to address the probabilistic description of chaotic dynamics.
Contact
Federico Mogavero
10/11/2023
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Thesis :
Funding :
28
Exploring the interiors of ice giant planets with atomistic simulations
Domaines
Condensed matter
Statistical physics
Physics of liquids
Relativity/Astrophysics/Cosmology
Nouveaux états électroniques de la matière corrélée
Kinetic theory ; Diffusion ; Long-range interacting systems
Type of internship
Théorique, numérique Description
The internship offers the possibility to study materials at high pressures and temperatures as found in ice giant planets such as Uranus, Neptune and their exoplanetary analogues. You will learn the foundations of the atomistic simulation technique we apply in our research – density functional theory molecular dynamics. We will compute thermodynamic, structural, and transport properties of hydrogen sulfide using high-performance computing clusters. At the same time, you will gain some insights on planetary modeling and high-pressure experiments (e.g. at LULI 2000).
Contact
Mandy Bethkenhagen
09/11/2023
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Thesis :
Funding :
29
Bruit du papier froissé
Domaines
Soft matter
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
L'objectif du stage est d'élucider le bruit sec et intense associé au froissement d'une feuille, d'un film ou d'une plaque, au cours duquel l'énergie élastique se concentre en déformations singulières (plis, cônes, etc...) qui évoluent et s'accompagnent souvent d'endommagement plastique. L’enjeu de la compréhension fine de ce phénomène est de déterminer dans quelle mesure la signature acoustique de ce type d’évènement élastique violent peut permettre d’en déterminer les causes (énergie libérée, type de singularité, localisation) mais aussi éventuellement les propriétés élastiques et dissipatives du matériau. Une première étape de ce stage sera de caractériser expérimentalement le rayonnement acoustique dans l’air d’ondes élastiques générées dans une plaque mince et de le confronter à la théorie du rayonnement. Des ondes d’amplitude finie seront ensuite employées pour caractériser le rayonnement de plaque dans un régime non-linéaire de déformation. Finalement, des défauts que l’on retrouve sur les films froissés seront créés et annihilés à la surface d’une plaque et le son résultant de leur formation ou de leur disparition sera enregistré et analysé grâce à la compréhension des études précédentes. Ces expériences pourront bénéficier au besoin de la chambre anéchoïque du laboratoire. Nous recherchons une étudiante ou un étudiant motivé par les expériences et les problématiques multiphysiques (acoustique, élasticité, singularités).
Contact
Régis Wunenburger
Laboratory : Institut d'Alembert -
Team : Fluides Complexes et Instabilités Hydrodynamiques
Team Website
Team : Fluides Complexes et Instabilités Hydrodynamiques
Team Website
08/11/2023
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Thesis :
Funding :
30
Retournement temporel des ondes amplifié (par « freezing » gravitaire)
Domaines
Condensed matter
Physics of liquids
Nonequilibrium statistical physics
Non-linear optics
Non-equilibrium Statistical Physics
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
Nous avons introduit un nouveau concept permettant le retournement temporel des ondes appelé Miroirs Temporels Instantanés (MTI). Le principe s’appuie sur une modification brusque la vitesse de propagation des ondes dans un milieu pour induire la production d’ondes retournées temporellement qui se refocalisent sur les sources. Nous avons également implémenté ce concept avec des ondes hydrodynamiques. L’application brutale d’un pic d’accélération verticale permet de générer un MTI sur les ondes de surface qui se refocalisent sur la source.
Récemment, l’équipe de Nader Engheta (Penn State Univ., USA) avec qui nous collaborons, a montré théoriquement qu’il était possible de générer un MTI en électromagnétisme avec un pulse de permittivité négative [2]. Durant ce pulse, les ondes, qui se propageaient dans le milieu, s’immobilisent et croissent de façon exponentielle. Lorsque le pulse s’arrête, les ondes amplifiées repartent dans le sens de propagation initiale mais également de façon contra-propagative en « remontant le temps » jusqu’à leur source initiale.
Le but de ce stage est de réaliser avec des ondes hydro ce concept en accélérant verticalement le liquide. Il s’agit de monter l’expérience et de caractériser le phénomène (notamment l’amplification). Ce stage peut être poursuivi en thèse dans des expériences de contrôle temporel des ondes (financement Fondation Simons).
Contact
Emmanuel Fort
08/11/2023
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Thesis :
Funding :
31
A non-quantum computer based on a coherent Ising machine
Domaines
Condensed matter
Statistical physics
Physics of liquids
Quantum Machines
Nonequilibrium statistical physics
Quantum optics
Non-equilibrium Statistical Physics
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
Quantum computing, and quantum-inspired computing, could be the new frontier in answering complex optimization problems that are historically unsolvable on classical computers. Today’s fastest computers may take millennia to conduct highly complex calculations (NP-hard problems), including combinatorial optimization problems involving many variables. The Coherent Ising Machine (CIM) is the most promising solution to date.
The aim of this project is to implement a CIM with water waves and controllable electrostriction. Using little modulated electric rod above the surface it is possible to create “spins” with arbitrary phase and positions. This project is experimental and aim to build this wave computer. It is possible to pursue with a funded thesis.
Contact
Emmanuel Fort
08/11/2023
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Thesis :
Funding :
32
Stability of Thin liquid films: silicone coatings for glass
Domaines
Soft matter
Type of internship
Expérimental et théorique Description
Coatings of liquids on surfaces such as glass are commonly used in manufacturing processes. The stability and homogeneity of these liquid films is of course crucial to these applications. In the case of silicone oils coating glass, a rough estimate of the long-range interactions such as Van der Waals’ shows that such films should bear a uniform thickness at equilibrium: repulsive interactions should tend to a flat thick film. However, in practical situation, initially heterogeneous films never get uniform in a timely manner. As examples, defects on glass substrates lead to thickness heterogeneities that grow over time rather than heal (Figure, left). When starting from a collection of droplets sprayed onto a flat substrate (shown as dark blue disks in Fig/right), a nanometer-thick film first spreads around the droplets (yellow and cyan), and delays the spreading and coalescence of the droplets.
The internship aims at gaining insights into the behavior of silicone oil on glass and to elucidate the mechanisms underlying the time evolution of such coatings. To do so, model systems will be used (plane glass or silicon wafers, well-characterized silicone oils), and experimental set-ups will be developed, in order to measure and model the time variation of silicone oil coatings at all scales.
Contact
Emilie VERNEUIL
08/11/2023
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Thesis :
Funding :
33
Foam stability : from bubbles in a macro foam to single liquid films
Domaines
Soft matter
Type of internship
Expérimental et théorique Description
Processes involving liquids often face unwanted foaming issues (eg lubrication), while foaming is instead desired when intimate mixing of gas and liquid phases is needed (eg. chemical reaction with O2). Hence, controlling the bubble lifetime is crucial to applications. Extensive studies have been conducted on aqueous foams stabilized by surfactants, and have unveiled intricate mechanisms due to molecular adsorption of surfactants at the air/liquid interface. Recently, foaming of liquid mixtures has emerged as a model system to isolate some of the physical mechanisms ensuring bubble stability. Indeed, interfacial effects due to evaporation can be minimized, delays in interfacial adsorption are suppressed, thereby reducing the couplings between bulk and interface transfers. In addition, foaming of liquid mixtures is relevant to a large number of practical situation in which foams exist without adding surfactants.
The internship aims at further describing the physical mechanisms acting to stabilize foams of two mixed liquids [1]. To do so, we will perform experiments to quantitatively relate the lifetime of a bubble in a macroscopic column of foam (Fig A) to that of a single suspended liquid film (Fig B). We will particularly explore the effects of the bubble radius which sets the curvature and hence the capillary pressure gradients. These experiments will be analyzed and interpreted to improve our understanding of the stabilizing mechanisms in oil foams.
Contact
Emilie VERNEUIL
08/11/2023
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Thesis :
Funding :
34
Investigation of laser-produced magnetized collisionless shocks and associated particle acceleration
Domaines
Kinetic theory ; Diffusion ; Long-range interacting systems
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
Context:
Collisionless shocks are ubiquitous in the Universe. Charged particles can be accelerated to high energies by collisionless shock waves in astrophysical environments, such as supernova remnants. With the development of high-power lasers and magnetic field generation, laboratory experiments can play a central role in bridging the gap between theoretical models and astrophysical observations by providing data that helps us to improve our understanding of shock formation, as well as the associated particle energization mechanism [1-3].
Proposed work:
The internship is part of an ongoing effort of investigating laser-produced collisionless shocks in a magnetic field of tens of Tesla, both experimentally with high-power lasers worldwide, e.g., LULI2000 (FR), VULCAN (UK), and TITAN (US); and numerically with fully kinetic particle-in-cell simulations performed with the code SMILEI [4].
Contact
Julien Fuchs
07/11/2023
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Thesis :
Funding :
35
Investigation of the laser cross-talk in a magnetized plasma
Domaines
Kinetic theory ; Diffusion ; Long-range interacting systems
Type of internship
Expérimental et théorique Description
Context:
Plasma is a non-linear medium [1], where light waves can couple to plasma waves. There exists a whole range of laser-plasma interaction (LPI) phenomena, from filamentation, stimulated Brillouin scattering (SBS), stimulated Raman scattering (SRS), to cross-talk and braiding between laser beams [2] or cross-beam energy transfer (CBET) [3] between neighbor laser beams. Improving our knowledge of all these effects is not only important from a fundamental perspective, but also from a practical one in the frame of Inertial Confinement Fusion (ICF), where it is critical that as much as possible of the laser energy be transferred homogeneously to the fuel.
Proposed work:
The internship is part of an ongoing effort of investigating laser propagation and LPI in a magnetic field of tens of Tesla [4], both experimentally with high-power lasers worldwide, e.g., LULI2000 (FR) and TITAN (US); and numerically with fully kinetic particle-in-cell simulations performed with the code SMILEI [5] and magnetohydrodynamic (MHD) simulations with the code FLASH [6].
References:
[1] Turnbull, D., et al., PRL 118, 015001 (2017).
[2] Nakatsutsumi, M., et al., Nat. Phys. 6, 1010 (2010).
[3] Michel, P., et al. Phys. Plas. 17, 056305 (2010).
[4] Yao, W., et al. PRL 130, 265101 (2023).
[5] Derouillat, J., et al., Comput. Phys. Commun. 222, 351-373 (2018)
[6] Fryxell, B., et al. The Astrophysical Journal Supplement Series 131.1, 273 (2000)
Contact
Julien Fuchs
07/11/2023
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Thesis :
Funding :
36
MASSIVE BLACK HOLES IN REALISTIC LISA DATA: MODFIED GRAVITY OR INSTRUMENTAL ARTIFACTS ?
Domaines
Relativity/Astrophysics/Cosmology
Type of internship
Théorique, numérique Description
LISA is a future space-based detector that will fly in the mid-2030s and detect gravitational waves at low frequencies, targeting massive black hole binaries with masses of millions of solar masses. These signals will be extremely loud compared to the detections of stellar-mass black holes by LIGO/Virgo, and LISA will bring us in an era of high-precision gravitational-wave astronomy, enabling tests of general relativity (GR) with an unprecedented precision. However, most simulations of LISA data analysis work with an idealized instrument. In reality, the data will be complex, with non-stationarities and glitches, and with superposed signals. Hence the question we will address in this internship: could we mistake superposed signals or instrumental artefacts with deviations from GR ? Can we design workarounds in our analysis, to unleash LISA’s full potential ? The internship will be undertaken in the GW group at the L2IT in Toulouse, which is composed by internationally well-known researchers, and currently counts 3 postdocs, 4 PhD students and 3 software engineers. Weekly interactions with group members and other L2IT members will expose the student to a highly dynamical envirnmeoment where the she/he will be able to affine her/his research skills.
Contact
Nicola Tamanini
07/11/2023
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Thesis :
Funding :
37
COSMOLOGY AND GRAVITATIONNAL WAVES: NEW TESTS OF THE STANDARD COSMOLOGICAL MODEL
Domaines
Relativity/Astrophysics/Cosmology
Type of internship
Théorique, numérique Description
Gravitational waves constitute a new observational instruments which convey new information about our Universe and its structures in a completely complementary way with respect to standard electromagnetic observations. In particular gravitational waves emitted by the mergers of black hole and neutron star binaries can be used to test how fast the universe expands at different epochs of its evolution. Consequently different cosmological models can be tested with gravitational waves, with new possible insights into the contemporary mysteries of the Universe such as dark energy, dark matter, the Hubble tension, and others. This internship project aims at investigating standard and alternative scenarios describing the evolution of our Universe using gravitational-wave observations from current and next generation gravitational-wave observatories. The student will become familiar with the basics of the theory of gravitational waves and with Bayesian statistical inference, she/he will get acquainted with some of the advanced theoretical and computational state-of-the-art techniques used in gravitational-wave cosmology. She/he will also have the opportunity to work within the framework of large international collaborations dedicated to observe gravitational waves, in particular the LIGO-Virgo-KAGRA Collaboration, the LISA Consortium and the Einstein Telescope Consortium.
Contact
Nicola Tamanini
07/11/2023
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Thesis :
Funding :
38
BRIDGING THE GAP: USING SPECTROSCOPY TO ENHANCE GRAVITATIONAL WAVE COSMOLOGY
Domaines
Relativity/Astrophysics/Cosmology
Type of internship
Théorique, numérique Description
One of the most significant challenges in cosmology is the difference in Hubble constant values resulting from different measurement methods. Gravitational waves (GWs) offer an independent approach to determine the Hubble constant and resolve this discrepancy. The key to employing GWs for cosmological purposes lies in the direct measurement of the source’s distance through GWs, which can then be combined with the redshift of the galaxy from which the GW originated. Even when the exact host galaxy cannot be identified, considering all possible host candidates allows for a reliable estimate. By aggregating numerous such estimates from various GW events, we can progressively approach a resolution of the Hubble tension. During the ongoing observation period of the GW detector network, we are already detecting sources at distances where our knowledge of galaxies may not be detailed enough to provide an accurate Hubble constant estimate. In this project, you will investigate the potential benefits of collaborating with astronomical telescopes to conduct spectroscopic observations, obtaining more precise redshift values for galaxies. You will learn how gravitational-wave cosmology works, what are the capabilities of state-of-the-art telescopes, how to combine GW data with EM observations, and how to work in a large international collaboration. Based on this study, a partnership between the global GW detector network and some of the world’s largest telescopes could be established.
Contact
Nicola Tamanini
07/11/2023
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Thesis :
Funding :
39
Collective effects in fish
Domaines
Biophysics
Physics of liquids
Physics of living systems
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Théorique, numérique Description
The collective behavior of fish is an astonishing example of coordinated movement that forms spontaneously on a large scale despite limited communication between individuals. In situ studies have identified the benefit of such schooling behavior: energy saving for swimming, visual effect for fighting a predator. Recently, experimental studies have also made it possible to test interaction models between individuals in a simple environment. Some phases of collective movements have been characterized by different dynamic models of non-equilibrium systems. We have recently proposed a model, purely orientational, which shows the gain in rheotaxis performance in the presence of collective interactions. For this internship, we propose a numerical work. The objective of the internship is to study the dynamics of groups of fish in 3D. A preliminary work has already been carried out and shows the emergence of new phases that appear and do not exist in 2D (i.e. the majority of models published in the literature) like elongated milling structures or turning phases that appear because of the third dimension. A phenomenon that has to be understood!
Contact
Aurélie Dupont
07/11/2023
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Thesis :
Funding :
40
Challenging collective behavior of fish: evacuation through two doors
Domaines
Biophysics
Physics of living systems
Non-equilibrium Statistical Physics
Type of internship
Expérimental Description
The collective behavior of fish is an astonishing example of coordinated movement that emerges spontaneously on a large scale despite limited communication between individuals. Recently, we have challenged the collective behavior of fish by forcing the fish school to pass through a bottleneck. This experiment revealed that, unlike humans, fish still respect social distance upon emergency evacuation which renders the evacuation more efficient. To go further and reveal cognitive effects, we want to repeat the evacuation experiments but with two openings. By varying the opening size and the distance between them, we aim at characterizing the gregarious instinct of fish.
Contact
Aurélie Dupont
07/11/2023
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Thesis :
Funding :
41
Evacuation of a crowd, the fish-bubble analogy
Domaines
Biophysics
Soft matter
Physics of liquids
Physics of living systems
Type of internship
Expérimental Description
We are interested in the case of schools of fish and more particularly in their evacuation through an opening of a size comparable to the size of the fish. We have recently shown that the escape of fish is analogous to that of bubbles. We would like to further explore this analogy and its limits. The aim of the internship will be to analyze the statistics of evacuation time intervals, in the same way as we did for fish, and see whether the model proposed for fish is valid for bubbles. The physical questions are many and open: how intermittent is bubble evacuation? Can we observe blocking phenomena such as those seen with active particles or grains? What are the interactions between slits and their consequences on bubble evacuation rates?
Contact
Aurélie Dupont
07/11/2023
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Thesis :
Funding :
42
Neural activity in the retina as a statistical-mechanics problem
Domaines
Condensed matter
Statistical physics
Biophysics
Physics of living systems
Type of internship
Théorique, numérique Description
Modern electrophysiological recording techniques have made it possible to simultaneously measure the activity of hundreds of neurons in the brain. To make sense of these massive recordings, appropriate techniques of data analysis and machine learning are necessary to reveal the relevant information contained therein. Because one of the main challenges of this objective are strong correlations between many interacting units, statistical mechanics is an excellent tool to tackle it, and has in fact been used in the realm of neuroscience for about four decades.
In our work, we use maximum-entropy models, and extensions thereof to quantify the information about the stimulus contained in neural activity. This requires the fitting of models faithfully reproducing the statistics of numerous neurons, which is a hard task. However, maximum entropy models are static by nature, and this contrasts with the fundamentally dynamic nature of the stimuli in the real world. The topic of the internship project is therefore to extend the existing models to capture this temporal variability. Under our guidance, the intern will combine concepts stemming from statistical mechanics, information theory and machine learning to understand the data from ex-vivo retinas collected in our team.
Contact
Ulisse Ferrari
06/11/2023
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Thesis :
Funding :
43
Power Production in living systems: a biomimetic model of optimisation constrained by resource management
Domaines
Biophysics
Physics of living systems
Type of internship
Expérimental et théorique Description
animal locomotion can be described using the formalism of an energy conversion machine. We can then derive a number of reduced observables enabling their characterization. 1/number of muscle fibers, 2/high-speed dissipation, 3/basal consumption.
Based on literature data, we want to systematically test the model, and in particular develop missing approaches: unsteady response, training, loads...
Contact
Eric Herbert
06/11/2023
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Thesis :
Funding :
44
Growth Dynamics in P. anserina : A living, Growing and Branching Network
Domaines
Biophysics
Physics of living systems
Type of internship
Expérimental et théorique Description
The growth of a fungal network is based on simple rules and generates highly complex patterns. The network is optimized for access to nutrients and diffusion of the spores produced for reproduction. The orientation of the apexes is crucial to the homogeneous dissolution of the network. The aim of this internship is to use time-lapse films obtained in the laboratory to extract the dynamics of apex interactions in the vicinity of hyphae.
Contact
Eric Herbert
06/11/2023
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Thesis :
Funding :
45
Phase Transitions in Turbulence
Domaines
Statistical physics
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Théorique, numérique Description
Two dimensional turbulence has the magnificent property to self organize in large structures unlike three dimensional turbulence that leads to disorganization. When strongly anisotropic flows are considered the flow has a hybrid behavior that is not yet understood. Varying the anisotropy turbulence displays phase transitions from a self-organizing state to disorganized state. The present project is going to investigate such phase transitions at different limits in order to understand the flow behavior close to the critical points. The work will be based on numerical simulations of the Navier-Stokes equations and the use of simplified theoretical models.
Contact
Alexandros Alexakis
06/11/2023
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Thesis :
Funding :
46
Précurseurs de rupture dans les gels de protéines sous fatigue.
Domaines
Condensed matter
Statistical physics
Soft matter
Physics of liquids
Non-equilibrium Statistical Physics
Type of internship
Expérimental Description
Précurseurs de rupture dans les gels de protéines sous fatigue. (pdf ci joint)
Les gels de protéines sont constitués d'assemblages de protéines dispersés dans l'eau et liés par des
interactions attractives en un réseau de brins micrométriques s'étendant dans l'espace. Ces solides mous
sont utilisés dans des applications très variées, allant des produits alimentaires aux produits cosmétiques
et pharmaceutiques. Une bonne résistance mécanique à une contrainte oscillante est essentielle pour
leur utilisation pratique. Malgré d’importants progrès récents, les mécanismes fondamentaux qui
sous-tendent la rupture des gels restent mal compris. Ce stage vise à identifier les précurseurs
microscopiques de la rupture dans les gels de protéines grâce à des expériences combinant rhéologie
et microscopie confocale sous cisaillement ou compression oscillante. Nous quantifierons
l’accumulation de l’endommagement à travers les réarrangements de particules et les variations locales
de la concentration en protéines conduisant à la rupture finale.
Contact
Thomas Gibaud
Laboratory : laboratoire de physique, ENS de Lyon - umr 5672
Team : ENS de Lyon, Physique
Team Website
Team : ENS de Lyon, Physique
Team Website
06/11/2023
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Thesis :
Funding :
47
Swimming in fluctuating lanes: How do bacteria navigate changing environments?
Domaines
Condensed matter
Statistical physics
Biophysics
Soft matter
Physics of liquids
Nonequilibrium statistical physics
Physics of living systems
Non-equilibrium Statistical Physics
Kinetic theory ; Diffusion ; Long-range interacting systems
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Théorique, numérique Description
Microorganisms, such as bacteria or microalgae, are often found in complex environments: from maze-like structures in soils to serpentine channels in the intestine. Numerous works have characterized the motion of microorganisms in the bulk. However, studies in realistic environments remain scarce. Recently [1], it was found that bacteria in porous media (a microscale maze-like 3D structure) exhibit a peculiar behavior and get trapped in specific spots. This is due to the time to flip their swimming direction.
In addition, in Nature, environments dramatically evolve in time, from rainfalls which induce flows to soil mazes that continuously reorganize due to the presence of other microorganisms which create jams or open up pathways.
Toinvestigate the motion of microorganisms in such fluctuating environments, we will explore a minimal model of active particles moving through a wiggling channel (=swimming in a fluctuating lane). We will study the diffusion and the drift of the particles according to the speed of the fluctuations [2]. We expect to uncover interesting regimes where motion is increased by collisions with the channel walls. We also expect odd behaviors associated with the interplay between different time scales in the system. We will characterize these different regimes. This internship will be in collaboration with Ruben Zakine (Ecole Polytechnique).
Contact
Sophie Marbach
06/11/2023
/
Thesis :
Funding :
48
Counting Bacteria in Boxes: How do bacteria colonize surfaces?
Domaines
Condensed matter
Statistical physics
Biophysics
Soft matter
Physics of liquids
Nonequilibrium statistical physics
Physics of living systems
Non-equilibrium Statistical Physics
Kinetic theory ; Diffusion ; Long-range interacting systems
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
The colonization of surfaces by bacteria raises many societal issues related to antibiotic resistance and waste management. Our grasp on initial surface establishment, crucial to address colonization at its roots, is limited. In this early stage, bacteria number fluctuations – due to surface adhesion, division, or motility – are large, challenging current analysis tools and theories. These fluctuations can result in more tight or sparse aggregates, dramatically affecting long-term colonization dynamics. How do individual dynamics and intermittent adhesion determine these aggregate patterns and collective growth?
To make progress, we will use a new analysis technique relying on number fluctuations called the ``Countoscope’’ [2]. The principle is like a game! We count the number N(t) of particles (bacteria, colloids or cells) in analysis boxes over time. The number of particles in a box fluctuates due to microscopic dynamics such as diffusion, adhesion, etc. Interpreting N(t) requires building new theories in this colonization context. These theories can then disentangle processes and quantify dynamics from the time-dependent statistics of N(t).
Here we will, on the one hand, count the number of bacteria in various box sizes on experimental images. On the other hand, we will develop minimal models to interpret these counts. This internship will be in collaboration with Eleonora Secchi (Zurich), who investigates bacteria on surfaces in microfluidic channels.
Contact
Sophie Marbach
06/11/2023
/
Thesis :
Funding :
49
Micromanipulation study of RNA energy landscape modulation by epigenetics
Domaines
Statistical physics
Biophysics
Soft matter
Physics of living systems
Type of internship
Expérimental Description
Magnetic tweezers are a tool enabling real-time monitoring of nucleic acid extension on a single-molecule scale, at several hundred Hz. They are perfectly suited for tracking the temporal evolution between different molecular conformations of nucleic acids and measuring their energy differences as we already demonstrated. What's more, by imposing a tensile force on the molecules studied, it is possible to modify the energy profile and bring out minority conformations, i.e., those of higher energy.
The proposed project will first study of the influence of methylation on RNA conformational flexibility at the single molecule level with magnetic tweezers. After the quantification of the conformational energy profile of the RNA, the influence of RNA methylation on protein binding on the sequence used will be investigated.
Contact
Jean Francois Allemand
06/11/2023
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Thesis :
Funding :
50
On-chip model of mucociliary clearance
Domaines
Biophysics
Soft matter
Physics of liquids
Physics of living systems
Type of internship
Expérimental Description
Chronic respiratory diseases caused 4 million deaths worldwide in 2019. Pulmonary disease treatments are administered by inhalation in particulate formulations. However, mucociliary clearance (MCC) acts as an effective physical barrier that prevents drugs from reaching the target cells. This mechanism relies on the beating of cilia on the bronchi surface, which allows the displacement of the overlying mucus layer. Inhaled drugs are thus trapped by the mucus and evacuated from the airways.
This project aims to model the mechanism of mucociliary clearance using a microfluidic chip, to assess drug penetration through the moving mucus and thus provide a screening platform for new drug formulations. We chose to design a non-cellular MCC model, which will provide an easy and reproducible alternative to cell-based MCC models.
The chip is composed of a circular channel covered with magnetic micropillars that can be remotely actuated via an underlying rotating magnet. Preliminary experiments showed that such an actuation of the pillars results in a beating similar to that of bronchial cilia.
The trainee will address the following scientific/technical questions:
- What is the velocity profile of mucus in the chip?
- How to mimic particle deposition on the bronchi during inhalation, with the chip?
- Does the chip reproduce the particle behaviour observed on cell-based MMC models?
The trainee will be co-supervised by Dr Marine Le Goas, working in Dr Berret’s group
Contact
Jean-François Berret
31/10/2023
/
Thesis :
Funding :
51
Exploring Cellular Mechanics: Insights into Metastatic Breast Cancer Biomarkers
Domaines
Biophysics
Soft matter
Physics of liquids
Physics of living systems
Type of internship
Expérimental et théorique Description
The Challenge: Cancer stands as a global health challenge, responsible for a staggering 25% of all deaths worldwide. Metastasis, the transformation of cancer cells into invasive agents capable of spreading and forming secondary tumors, remains a formidable barrier to defeating cancer. While treatments and therapies have made strides in addressing primary tumors, metastatic disease remains largely incurable, contributing to over 90% of cancer-related deaths.
Where Physics Meets Biology: In the last decade, a groundbreaking idea has emerged in biophysics: cancer cells possess a unique trait - they are softer than their healthy counterparts. This implies that the elasticity of cancer cells is lower than that of healthy cells. This characteristic is thought to enable metastatic cells to navigate through the tumor, infiltrate the bloodstream, and ultimately establish secondary tumors.
Our Mission: Our mission is to bridge the gap between biophysics and oncology by quantitatively assessing the invasive and metastatic potential of patient-derived cells. This information is crucial for diagnosing the aggressiveness of cancer.
What You'll Work On: As an intern in our group, you will have the opportunity to delve into cell biomechanics and cancer research. We are focusing on human breast cancer epithelial cell lines exhibiting varying metastatic potentials. Additional work will be on genetically modified human breast cancer cells using CRISPR technology.
Contact
Jean-François Berret
31/10/2023
/
Thesis :
Funding :
52
Coherent quantum emitter coupled to a nanophotonic waveguide
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Quantum optics
Non-linear optics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
Photons have long been favored as carriers of information due to their non-interacting nature. Tradition- ally, atoms have served as the primary means to manipulate and process quantum information carried by photonic qubits. However, recent groundbreaking advancements in solid-state emitters such as color centers, quantum dots, and molecules have ushered in a new era of highly coherent interaction with light, akin to atomic-level interactions.
Moreover, the seamless integration of solid-state emitters into nanophotonic structures has unlocked the potential for achieving remarkably efficient light-matter interactions [1]. Amongst them, nanofibers have attracted attention due to their guided evanescent field that enables efficient coupling of emitters placed at their vicinity. This breakthrough not only facilitates the creation of high-performance single- photon sources but also enables the exciting prospect of photon-photon interactions[2].
Within the nanophotonic research team at LKB, we have cultivated expertise in the production of nanofiber waveguides and their precise coupling with solid-state emitters [3, 4]. This specialized focus empowers us to drive advances in single-photon quantum information processing
Contact
Quentin Glorieux
31/10/2023
/
Thesis :
Funding :
53
Topological 3D multifold semimetals beyond Weyl/Dirac semimetals
Domaines
Condensed matter
Nouveaux états électroniques de la matière corrélée
Topological materials, Quantum Transport, Cavity Quantum Electrodynamics
Type of internship
Théorique, numérique Description
In many topological semimetallic materials, the electrons behave as 3D Weyl/Dirac ultrarelativistic pseudo-spin-S quantum particles such that the electron's wavefunction carries a Berry curvature monopole that is at the origin of many anomalous low and high magnetic field magnetotransport properties.
In a recent work we have predicted [1] that new kinds of massless quantum particle can exist, in which now the Berry curvature is a singular multipole (dipole, quadrupole, octupole). For such systems we have predicted distinct magnetotransport as compared to those of pseudospin-S Dirac/Weyl semimetals. We have also shown that “multifold dipole" semimetals naturally appear at the transition between two distinct topological Hopf- insulating phases [2].
The aim of this PhD project is to continue the exploration of this novel family of multifold semimetals associated to singular multipoles of Berry curvature, using analytical band-topological and numerical methods on tight-binding and continuum models. It consists to systematically construct models and explore their key features such as symmetries and topological properties and reveal their consequences on various physical properties. The project also envisions a challenging study of the stability of such semimetals to the breaking of symmetries and the electron-electron interactions.
[1] A.Graf and F.Piéchon, Phys.Rev.B 108,115105 (2023).
[2]A.Nelson,T.Neupert,A.Alexandradinata,and T.Bzdušek, Phys.Rev.B 106,075124(2022).
Contact
Frederic Piechon
30/10/2023
/
Thesis :
Funding :
54
Flow-induced instabilities of kirigami sheets
Domaines
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
In the field of engineering, there is a growing interest for flexible components over rigid ones, in devices designed to operate within fluid flow. The capacity of these components to deform makes them more resilient and adaptable to fluctuating fluid environments. Nevertheless, a major challenge lies in understanding how these flexible objects deform when subjected to fluid loading and in being able to control their responses. The objective of the internship is to investigate static and dynamic flow-induced instabilities of kirigami sheets (inspired by the Japanes art of paper cutting), to ensure the structural integrity of those functional components, or alternatively for applications such as energy harvesting.
Contact
Sophie Ramananarivo
30/10/2023
/
Thesis :
Funding :
55
Flow control using kirigami sheets
Domaines
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
The ability to manipulate flow fields is of importance in various engineering applications, influencing efficiency, performance, and safety. The objective of this internship is to investigate the impact of kirigami sheets (inspired by the japanes art of paper cutting) on fluid dynamics and explore their potential for passive flow control.
Contact
Sophie Ramananarivo
30/10/2023
/
Thesis :
Funding :
56
Numerical modelling of granular avalanches through a forest of deformable pillars
Domaines
Soft matter
Type of internship
Théorique, numérique Description
This projet proposes to investigate the downslope flow of a granular material through a forest of flexible fibres in an inclined plane geometry, and study how the elasticity of the fibres, as well as the frictional interactions between the grains and the fibres, can impact the granular flow. It focuses on numerical modelling and simulations using the Discrete Element Method coupled with non-smooth contact solvers developed in the team.
The numerical study will be supported by experimental measurements in the context of a collaboration with the FAST lab.
Contact
Thibaut METIVET
27/10/2023
/
Thesis :
Funding :
57
Avalanches of fibre-reinforced granular materials
Domaines
Soft matter
Type of internship
Expérimental Description
This project proposes to study the effect of fibre reinforcement on the avalanche dynamics of granular materials.
Contact
Baptiste Darbois Texier
27/10/2023
/
Thesis :
Funding :
58
Spectral broadening of single colloidal nano-emitter under high excitation
Domaines
Condensed matter
Quantum optics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental et théorique Description
CdSe/CdS core/shell nanocrystal are excellent bright nano-emitters, awarded by the Nobel Price 2023. At room temperature, they behave as high quantum efficiency single photon source thanks to the electronic confinement and efficient Auger processes. Single photon emission can be described by the recombination of a single exciton within a simple two-level system. Under low excitation power at room temperature, the emission linewidth is approximately Δ𝜆 ≈ 20 nm. However, by increasing the excitation power, emission spectrum broadens dramatically up to Δ𝜆 ≈ 150 nm. Moreover, the emission intensity grows non-linearly with increasing excitation power. The two- levels system paradigm fails for interpreting those features. We have recently developed a model based on the radiative recombination of multiple excitonic levels within a single nanocrystal , relying on statistical description of electron and hole populations in a quasi-equilibrium and on their recombination.
During the internship the student will consider different types of nano-emitter, quantum dots or quantum wells, and will study their emission under high excitation. He/She will then analyse the experimental datas using among others Bayesian methods, and extent our theoretical model.
During the PhD, in the framework of the ANR CoLIMe, starting in 2024, and in continuity of the internship, we will study strong coupling between multiexcitonic emission of those nanoemitters and plasmonic antennas.
Contact
Agnes MAITRE
26/10/2023
/
Thesis :
Funding :
59
Oscillations of a micro hydraulic jump
Domaines
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
The primary goal of this internship is to delve into the various cavity modes achievable within this system. By
altering the plate's shape, adjusting the number of jets, and exploring the interactions between the liquid and
the substrate, we can investigate the conditions that trigger the oscillations in the hydraulic jump, unlock the
various cavity modes it offers and build a liquid equivalent to Chladni figures.
This internship also offers the opportunity for continuation into a Ph.D. thesis, which will further address the
questions previously mentioned, as well as explore other aspects of microjets impacts.
Contact
Alexis Duchesne
26/10/2023
/
Thesis :
Funding :
60
Simultaneous 3D localization and 2D orientation determination for single-molecules super resolution microscopy
Domaines
Biophysics
Physics of living systems
Metrology
Type of internship
Expérimental Description
Super-resolution (SR) microscopy have revolutionized our understanding of the biological processes at the molecular level. Imaging single molecules and localizing their center with high precision allows the reconstruction of pointillist image of the sample with a resolution beyond the diffraction limit [1,2,3]. In order to capture the 3D nanoscale morphology of the whole cell, multifocus microscopy (MFM) has been proposed to instantaneously acquire the 3D localization of single molecules (SM) in cells within a volume of a few micrometers [4,5]. Still additional information such as molecular orientation can provide supplementary information relating the local molecular organization and arrangement to the biological function. One strategy to recover the orientation of single molecules is by polarimetric measurement [6]. A polarization-splitting scheme combined with SMLM allows to determine both the 2D localization and orientation of SM.
The aim of this internship is to retrieve the orientation measurement simultaneously with 3D positional information of single molecules in biological samples. The method will rely on combining MFM with polarization measurements at the different focal plane.
Contact
Bassam HAJJ
26/10/2023
/
Thesis :
Funding :
61
Probing the diffusion landscape in the nucleus of living cells
Domaines
Biophysics
Soft matter
Physics of living systems
Type of internship
Expérimental Description
Single-molecule localization microscopy (SMLM) offers a means to visualize (super-resolution) and follow (single-particle tracking) the dynamics of biological entities at the molecular scale. Within the nucleus, SMLM imaging revealed that biomolecules self-assemble and organize into condensates and compartments to perform specific tasks (e.g. transcription) or play a specific role (e.g. maintaining of genetic information), thus linking organization with function [1]. It is known that DNA organization and compaction play a role in orchestrating the different nuclear functions and gene expression by restricting the accessibility of nuclear players to specific genes. In cancerous cells, it was shown that DNA compaction and chromosome territories are massively altered. However, a single cell characterization of the physical property of the cell nuclear environment is still missing. The purpose of this internship is to map such environment at molecular scale by following the dynamics of inert particles of different sizes injected inside the nucleus.
Efficient 3D tracking of single particles in the nucleus will be performed using Multifocus microscopy (MFM) [2]. MFM allows simultaneous acquisition of 9 different focal planes on the same camera, thus covering the whole volume of a nucleus in a single acquisition.
Contact
Bassam HAJJ
26/10/2023
/
Thesis :
Funding :
62
Mutlicolor & Multifocus microscopy for single molecule imaging
Domaines
Biophysics
Physics of living systems
Metrology
Type of internship
Expérimental Description
The ability to control the wavefront at the output of an imaging system allows to correct the imaging system optical aberration but also to impose a controlled deformation to encode specific information in the recorded images. Diffractive optical elements (DOE) provide an efficient mean to manipulate light.
In multifocus microscopy (MFM) for instance [2,3], a DOE is placed in the back focal plane. It plays two roles: first, it splits the emission into a specific array of equal-intensity diffraction orders, and second it applies a specific deformation of the wavefront in each diffraction order. The grating splits the emission into several paths while imposing a specific defocusing or focusing power to each. In MFM multiple imaging planes are thus formed side by side on the same camera allowing a fast and sensitive volumetric imaging of biological samples. Still the wavelength-dependent diffraction properties of DOE can limit the use of MFM for multicolor applications [3]. The purpose of this internship is to explore new methods for the realization of achromatic DOE [5]. In addition, the use of DOE as a mean to detect and identify different fluorescent species with distinct spectral properties will be explored. Such developments will be further tested for single molecule imaging in real biological systems. We aim to study the molecular organization and interplay of several nuclear factors that are involved in nuclear organization.
Contact
Bassam HAJJ
26/10/2023
/
Thesis :
Funding :
63
Trous noirs artificiels dans les fluides quantiques de lumi`ere
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Relativity/Astrophysics/Cosmology
Quantum optics
Non-linear optics
Quantum gases
Type of internship
Théorique, numérique Description
Les photons sont d'excellents porteurs d'information, mais ils n'interagissent généralement pas entre eux.
Les atomes interagissent, mais ils sont difficiles à manipuler et ne bénéficient pas de l'arsenal de l'optique quantique pour détecter les fluctuations quantiques et l'intrication.
Notre approche pour marier ces deux systèmes pour la simulation quantique consiste à utiliser des exciton-polaritons dans des microcavités semi-conductrices.
Notre équipe utilise cette plateforme pour simuler des effets astrophysiques à proximité de trous noirs artificiels, avec de la lumière.
Contact
Quentin Glorieux
25/10/2023
/
Thesis :
Funding :
64
Artificial black holes in exciton-polariton fluids of light.
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Relativity/Astrophysics/Cosmology
Quantum optics
Non-linear optics
Quantum gases
Type of internship
Expérimental Description
Photons are great carriers of information but they usually don’t interact with one another.
Atoms interact but are hard to manipulate and do not benefit from the toolbox of quantum optics for detecting quantum fluctuations and entanglement.
Our approach to marry these two systems for quantum simulation is to use exciton-polaritons in semi-conductor microcavity.
Our team is using this platform to simulate astrophyics effects near artificial black holes with light.
Contact
Quentin Glorieux
25/10/2023
/
Thesis :
Funding :
65
Manipulation de cristaux d’ondes
Domaines
Condensed matter
Statistical physics
Physics of liquids
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Kinetic theory ; Diffusion ; Long-range interacting systems
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
La surface d'un bain vibré verticalement devient instable au-delà d’un seuil d’accélération (instabilité de Faraday) . Le motif ondulatoire obténu dépend de la forme du bain et résulte de la réflexion des ondes générées sur les parois. Lorsque l’on augmente la viscosité du liquide, un nouveau régime fascinant apparait. Les motifs à la surface du bain peuvent alors être interprétés comme un ensemble de sources localisées en interactions les unes avec les autres via les ondes quelles produisent. Ces « oscillons » interagissent uniquement avec leurs plus proches voisins et tentent de maintenir une distance entre elles d’une demi-longueur d’onde. Ces ondes agissent ainsi comme un ensemble de masses variables couplées. Le caractère particulaire de cet objet purement ondulatoire lui confère des propriétés fascinantes qui permettent de revisiter les domaines de la matière active, des milieux variables en temps, des systèmes dynamiques hors-équilibre ou de l’auto-organisation. Contrairement aux systèmes mécaniques, les oscillons peuvent notamment apparaitre ou disparaitre, et leurs interactions sont à l’origine même de leur existence. La richesse de ce système ouvre de nombreuses perspectives d’expériences. Pour ce stage, nous mettrons ce motif d’oscillons sous contrainte en faisant varier la surface du bain par déplacement d’une des parois. Nous étudierons les transitions de phase, les réorganisations et auto-organisations induites ainsi que la dynamique de ce cristal d’ondes.
Contact
Emmanuel Fort
25/10/2023
/
Thesis :
Funding :
66
Widely tunable ultra-stable and SI-traceable quantum cascade lasers for frequency metrology and mid- infrared precise spectroscopy: application to space, atmospheric and fundamental physics
Domaines
Quantum optics/Atomic physics/Laser
Metrology
Type of internship
Expérimental Description
Ultra-high resolution molecular spectroscopy is an interdisciplinary field with fascinating applications ranging from fundamental physics to astrophysics, earth sciences, remote sensing, metrology and quantum technologies. Among recent instrumental advances, the stabilization of quantum cascade lasers (QCLs) on optical frequency combs with traceability to primary frequency standards, a method recently implemented in our team, is a breakthrough technology. It offers an unprecedented level of precision in the mid-infrared, an essential region known as the molecular fingerprint region, which hosts a considerable number of intense vibrational signatures of molecules of various interests. This opens up prospects for carrying out fundamental physics tests and exploring the limits of the Standard Model, and for providing precise spectroscopic data on species of astrophysical or atmospheric interest, which is a crucial information for environmental and human health issues.
We have for instance recently measured rovibrational frequencies in methanol with 11-digits accuracy by carrying
out saturated absorption spectroscopy in a multi-pass cell and in a Fabry-Perot cavity enhanced spectroscopy, a
more than 4 orders of magnitude improvement compared to previous measurements reported in the literature.
Contact
Mathieu Manceau
24/10/2023
/
Thesis :
Funding :
67
The hidden mechanics of soft gels
Domaines
Soft matter
Type of internship
Théorique, numérique Description
Gels constitute a large portion of the materials around us: body tissues, food products, but also industrial glues and seals. At first glance, they are mechanically similar to other elastic materials. If you take a piece of gelatin, for instance, you can deform it by a small amount and it will return to its original shape. If you look closer, however, gels have a complex molecular structure. They are made of a crosslinked polymeric network swollen by a liquid solvent. As a consequence, their mechanical behavior is dictated by the coupling between the elastic deformations of the polymeric network and the flow of the solvent. For simplicity, they are often modeled as incompressible solids, and these models are then used to estimate, for instance, adhesion forces of cells living on soft tissues. Whether they truly behave as incompressible solids, however, is both difficult to asses and crucial for an accurate modeling. In this project, we will take a deep dive into gel mechanics. You will exploit recently collected experimental data, which tracks the 3D displacement of the polymeric network inside a silicone gel, to understand in which circumstances a gel can be modeled as an incompressible solid. This will involve numerically analyzing of the displacement of tens of thousands of tracers, and rationalizing the results within the framework of continuum mechanics. The results will be directly compared with existing numerical predictions.
Contact
Nicolas Bain
24/10/2023
/
Thesis :
Funding :
68
Precision Measurements and tests of fundamental physics with cold molecules
Domaines
Quantum optics/Atomic physics/Laser
Metrology
Type of internship
Expérimental Description
The master student will participate in the development of a new-generation molecular clock specifically designed
for precision vibrational spectroscopy of cold molecules in the gas phase. The proposed technology is at the
forefront of cold molecule research and frequency metrology, and opens possibilities for using polyatomic
molecules to perform tests of fundamental physics and explore the limits of the standard model. The apparatus will
be used in the first place for measuring the electroweak-interactions-induced tiny energy difference between
enantiomers of a chiral molecule, a signature of parity (left-right symmetry) violation, and a sensitive probe of dark
matter.
The master student will take an active role in various aspects of the developments of the experiment. She/he will:
- set up the mid-IR quantum cascade laser system at 6.4 μm to probe molecular vibrations in this spectral
region;
- perform first Doppler and sub-Doppler absorption spectroscopy on cold molecules produced at ~1 K in a
novel cold molecule apparatus, with a particular focus on well-chosen promising chiral and achiral organo-
metallic species and polycyclic aromatic hydrocarbons.
Contact
Mathieu Manceau
24/10/2023
/
Thesis :
Funding :
69
Quantum imaging with non-degenerated entangled photons
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Non-relativistic quantum field theory, quantum optics, complex quantum systems
Quantum information theory and quantum technologies
Quantum optics
Non-linear optics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Metrology
Type of internship
Expérimental Description
Quantum imaging (QI) is a rapidly developing field of research with stunning progresses and emerging societal applications. Quantum-enhanced imaging schemes harness the beneficial properties of entangled photon pairs allowing transferring amplitude and phase information from one photon state to the other. The technique is however still in its infancy and we propose to go beyond the state of the art. The main goal is to develop advanced QI protocols that exploits photon pairs at extreme wavelengths from near infrared to the visible down to the deep UV using a non-classical source based on high harmonic generation (HHG). The main objective of the internship will consist in using a pair of non-degenerated entangled photons at 2 harmonics from the HHG frequency comb to perform a quantum imaging experiment in the far field regime. We will study the possibility of transferring the sensing and resolution benefit from one spectral range to another one. Indeed, an intriguing question is about the spatial resolution achievable in the QI scheme, especially in the case of non-degenerate photon pairs. The quantum correlations between the two photons from the same harmonic generation process will be used to transfer amplitude and phase information between the two photons. In the diffractive regime, and in a "ghost diffractive imaging" configuration based on the coincident detection of the two entangled photons.
Contact
Hamed Merdji
24/10/2023
/
Thesis :
Funding :
70
Evidence of multipartite entanglement in semiconductor high harmonic generation
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Nouveaux états électroniques de la matière corrélée
Non-relativistic quantum field theory, quantum optics, complex quantum systems
Quantum information theory and quantum technologies
Quantum optics
Topological materials, Quantum Transport, Cavity Quantum Electrodynamics
Non-linear optics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Metrology
Type of internship
Expérimental Description
Quantum information science and imaging technologies reach some bottleneck due to limited scalability of non-classical sources. Future breakthroughs will rely on high production rate of various quantum states in scalable platforms. Generally, multipartite entanglement with N>2 suitable for quantum applications is difficult to achieve because of the low efficiency of the traditional schemes. Intrinsically, the HHG emission comes as a frequency comb and should exhibit N-partite entangled photons. Practically, the internship project will consist in extensively study the non-classical properties of the HHG process in a semiconductor for N>2. In the process, each emitted photon is a superposition of all frequencies in the spectrum, i.e., each photon is a comb so that each frequency component can be bunched and squeezed. The candidate will first develop and test entanglement and quantum correlations using the violation of Cauchy-Schwartz inequality. We will verify genuine multipartite entanglement of the photons in the time/frequency domain, by correspondingly measuring the longitudinal position as well as the frequency bandwidth. The approach will be further extended to verify multi-partite entanglement between even more optical modes. The Bell-like inequalities will therefore be generalized to witness entanglement between more than three mixed quantum states.
Contact
Hamed Merdji
24/10/2023
/
Thesis :
Funding :
71
Attosecond control of quantum states of light
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Non-relativistic quantum field theory, quantum optics, complex quantum systems
Quantum information theory and quantum technologies
Quantum optics
Topological materials, Quantum Transport, Cavity Quantum Electrodynamics
Non-linear optics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
High-harmonic generation is a light up-conversion process occurring in a strong laser field, leading to coherent attosecond bursts of extreme broadband radiation. As a new paradigm, attosecond electronic or photonic processes such as high-harmonic generation (HHG) can potentially generate non-classical states of light well before the decoherence of the system occurs. This could address fundamental challenges in quantum technology such as scalability, decoherence or the generation of massively entangled states with ultrafast processing. The internship will consist in realizing a platform that will allow controlling the carrier to envelope phase (CEP) of the laser that drives the semiconductor HHG emission. The CEP of the laser will allow controlling the non-classical state, in connection with our recent finding in various semiconductors (Theidel et al, submitted to Nature, in review). Single and multi-beam intensity cross-correlation, two-mode squeezing in the generated harmonic radiation, which depends on the laser intensity will be investigated. We will test the violation of the Cauchy-Schwarz inequality that realizes a direct test of multipartite entanglement in high-harmonic generation. The attosecond control of light states open the vision of quantum processing on unprecedented timescales, an evident perspective for future quantum optical computers. Only candidates motivated to follow with a PhD in this topic will be considered.
Contact
Hamed Merdji
24/10/2023
/
Thesis :
Funding :
72
Dynamique de radeaux granulaires dans un champs de vagues
Domaines
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
La dynamique d'un objet flottant en présence d'ondes de surface est un problème d'interaction fluide-structure de grande importance pratique, par exemple pour la stabilité des bateaux ou la dérive de la banquise. A plus petite échelle, ce problème intervient également dans la dérive et la dispersion de polluants (micro-plastiques) dans l'océan. Le stage proposé fait partie d'un projet de recherche visant à comprendre la dynamique d'objets flottants complexes (flexibles, composites) dans un champ de vagues. Plus spécifiquement, il s'agira de développer et d'analyser des expériences permettant de suivre la position et la forme de radeaux granulaires dans des ondes de surface gravitaires, et de proposer une modélisation physique pour décrire leur comportement.
Contact
Frederic Moisy
23/10/2023
/
Thesis :
Funding :
73
Interaction entre particules flottantes sur un liquide en oscillation
Domaines
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
Lorsque plusieurs particules flottent à la surface d'un liquide, elles ont tendance à s'agglomérer. Ce phénomène bien connu résulte de l'attraction capillaire, parfois appelée "effet Cheerios" : chaque particule se déplace sur une surface courbée par la présence des autres particules, cette courbure étant induite par le ménisque se formant sur la ligne de mouillage de chaque particule. Dans le cadre de ce stage, nous souhaitons étudier ce qu'il advient de cette attraction capillaire en présence de vibration. La motivation est ici de comprendre le comportement d'un agglomérat de particules flottantes soumises à un champ de vagues, question importante dans le contexte de la dispersion de polluants.
Contact
Frederic Moisy
23/10/2023
/
Thesis :
Funding :
74
Créer de la matière artifielle à base de photons dans un Fluide Quantique de Lumière
Domaines
Condensed matter
Nonequilibrium statistical physics
Quantum information theory and quantum technologies
Quantum optics
Non-linear optics
Quantum gases
Type of internship
Expérimental Description
Les photons sont d’excellents porteurs d’information, mais ils n’interagissent généralement pas les uns
avec les autres. Les atomes interagissent, mais ils sont difficiles à manipuler et ne bénéficient pas de
l’arsenal de l’optique quantique pour d´etecter les fluctuations quantiques et l’intrication. De nombreuses
approches ont été proposées pour marier ces deux systèmes en vue de simuler de la matière
condensée avec des photons fortement interagissant, mais à ce jour, la réalisation de matériaux
synthétiques composés de photons fait encore d´efaut.
Notre équipe vise cet objectif ambitieux, à savoir la création de Matiere Photonique Synthétique.
Nous proposons une opportunité de stage (suivie d'une thèse financée par l'ERC) pour étendre les capacités de notre plateforme à un nouveau niveau en augmentant de plusieurs ordres de grandeur les interactions effectives photon-photon et en entrant dans le régime des interactions fortes.
Contact
Quentin Glorieux
23/10/2023
/
Thesis :
Funding :
75
Using statistical physics to unravel how gene selection leads to robust developmental traits
Domaines
Statistical physics
Biophysics
Type of internship
Théorique, numérique Description
The complexity of biological systems is partly due to the intricate structure of interactions between thousands of genes. The topology of gene networks has been under scrutiny since the emergence of systems biology, but little progress has been made to connect theoretically large-scale statistical features of networks (typically, scale-freeness) to concrete functional and evolutionary properties. Using statistical physics, we are combining analytical and computational models to unravel how natural selection shapes gene interactions and give rise to robust developmental traits.
We built a statistical description for a population of individuals each described by their genes’ level of expression. In our model, the developmental dynamics of each individual were constrained by gene interactions encoded in an individual- specific matrix and included a noise source which accounted for the stochasticity inherent to developmental processes. We aimed at describing the long term population dynamics governed by the probability of each individual to survive, reproduce and mutate according to their developmental trajectories. Under reasonable assumptions, we deem it possible to derive an analytical model to obtain a reduced set of algebraic-Riccati-like equations for the developmental dynamics.
This model could represent a substantial improvement in theoretical systems biology, provided that the mathematical assumptions are biologically realistic.
Contact
Antoine Fruleux
Laboratory : LPTMS - UMR 8626
Team : Disordered systems, soft matter, interface physics
Team Website
Team : Disordered systems, soft matter, interface physics
Team Website
23/10/2023
/
Thesis :
Funding :
76
Synthetic Photonic Matter in a Quantum Fluid of Light.
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Statistical physics
Nonequilibrium statistical physics
Quantum optics
Non-linear optics
Non-equilibrium Statistical Physics
Hydrodynamics/Turbulence/Fluid mechanics
Quantum gases
Type of internship
Expérimental et théorique Description
Photons are great carriers of information but they usually don’t interact with one another. Atoms interact but are hard to manipulate and do not benefit from the toolbox of quantum optics for detecting quantum fluctuations and entanglement. Many approaches have been proposed to marry these two systems for quantum simulation of condensed matter with strongly interacting photons, but to date, the realization of large-scale synthetic materials made of optical photons is still missing.
Our team targets this exciting goal, namely the creation of Synthetic Photonic Matter.
We are offering an internship opportunity (followed by an ERC-funded PhD) to expand the capabilities of this platform to a new level by increasing by many orders of magnitude the effective photon-photon interactions and enter the strong interaction regime.
Contact
Quentin Glorieux
23/10/2023
/
Thesis :
Funding :
77
Nage des bactéries proche d'une surface
Domaines
Biophysics
Physics of liquids
Physics of living systems
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
Les bactéries motiles se propulsent dans les fluides à l’aide de flagelles. En fonction du nombre de flagelles, de leur direction de rotation ou encore de leur vitesse et leur synchronisation,
différents motifs de nage apparaissent. Le plus connu est celui des bactéries Escherichia coli qui est une succession de "runs" interrompus par des "tumbles". Ce motif n’est ni le seul ni le plus répandu.
Le premier objectif du stage sera de caractériser la nage de Sinorhizobia meliloti et de
Cabelleronia insecticola proche d’une surface et de les comparer avec la nage des bactéries Escherichia coli. Le second objectif sera d’étudier l’influence de ses motifs de nage sur le déplacement dans un gradient chimique. Pour cela, nous utiliserons une puce microfluique développée au laboratoire, qui permet d’observer la nage des bactéries dans un gradient chimique contrôlé. Ce système a déjà été employé pour étudier le chimiotactisme de Escherichia coli ce qui nous donnera un point de comparaison. A partir de ces dernières, nous déterminerons si le motif de nage favorise le chimiotactisme et nous discuterons les avantages évolutifs de ces motifs.
Contact
Harold Auradou
23/10/2023
/
Thesis :
Funding :
78
Test of quantum electrodynamics in strong Coulomb field
Domaines
Quantum optics/Atomic physics/Laser
Fields theory/String theory
Metrology
Type of internship
Expérimental et théorique Description
This internship will be centred in the preparation of a new experiment on high-accuracy x-ray spectroscopy of few electrons heavy ions for testing quantum electrodynamics (QED) in strong Coulomb field (the field of the highly charged ion).
On the one hand, to setup the acquisition system of the new detector and to make first tests with fluorescence targets and (possibly) with highly charged ions in our SIMPA installation in the Pierre et Marie Curie campus. On the other hand, the candidate will estimate the sensitivity to the nuclear size and deformation effects for the planned measurement to select the most interesting uranium isotopes to be studied. Some calculations will require the use of the MCDFGME code.
Contact
Martino Trassinelli
23/10/2023
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Thesis :
Funding :
79
Detecting new particles in quantum materials
Domaines
Nouveaux états électroniques de la matière corrélée
Type of internship
Expérimental Description
Quantum spin liquids are an exciting family of quantum materials with topological properties that offer novel solutions to quantum computing. In such materials, emergent particles and exotic phenomena arise from the interactions between huge numbers of electrons. This project will address how to detect novel particles in these new states of matter using a challenging experimental technique known as the "thermal Hall effect" measured in extreme conditions of magnetic field and temperatures. This effect represents the deflection of heat in a magnetic field and is thought to be a direct manifestation of these novel states of quantum matter. The project will also focus on developing a unique new approach for performing thermal experiments using nanofabrication processes that will be carried out in a clean room facility. This major milestone will open the door to many future perspectives in the field of quantum materials.
Contact
Gaël Grissonnanche
22/10/2023
/
Thesis :
Funding :
80
Uncovering a new law of physics in quantum materials
Domaines
Nouveaux états électroniques de la matière corrélée
Type of internship
Expérimental et théorique Description
One favored way to study unconventional superconductivity today is to investigate the preceding phase. Indeed, before they pair to form a superconducting state, electrons interact so strongly that they defy the standard theory of metals in a phase we call “strange metal”. Recent experiments have shown that strange metals host a scattering time between electron collisions that reaches a universal value known as the “Planckian limit”. To determine the origin of the Planckian limit, the aim of the project will be to measure and model the transport properties of unconventional high-temperature superconductors such as cuprates or more recently discovered nickelates under extreme temperature and magnetic field conditions.
Contact
Gaël Grissonnanche
22/10/2023
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Thesis :
Funding :
81
Visualiser l’auto-assemblage d’un virus en temps réel
Domaines
Biophysics
Type of internship
Expérimental Description
Les virus sont des agents biologiques étonnants constitués de centaines de briques élémentaires assemblées avec une précision atomique. Le projet de stage a pour objectif d’élucider la dynamique à l’équilibre de l’empaquetage du génome dans une capside virale icosaédrique à l’échelle de la molécule unique. Nous disposons d’un montage optique quasi unique combinant la microscopie de fluorescence à réflexion totale interne (TIRFM) et la microscopie interférométrique à diffusion (iSCAT) permettant de visualiser en temps réel des molécules par fluorescence et des molécules non nécessairement marquées par diffusion de la lumière. Des échantillons biologiques seront préparés puis des mesures par TIRFM/iSCAT seront réalisées à différentes concentrations en protéines virales. Les images seront analysées via d’éventuelles améliorations sur les codes existants pour déduire ensuite les grandeurs thermodynamiques. Idéalement, nous recherchons à estimer l’énergie libre d’interaction en fonction de l’état d’assemblage de la particule virale. Enfin, des expériences d’auto-assemblage en présence d’un agent d’encombrement seront initiées afin de s’approcher des conditions physicochimiques du milieu intracellulaire.
Contact
Guillaume TRESSET
20/10/2023
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Thesis :
Funding :
82
Experimental realization of quantum-squeezed states of light using optically-levitated nano-objects.
Domaines
Quantum optics/Atomic physics/Laser
Non-relativistic quantum field theory, quantum optics, complex quantum systems
Quantum optics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
During this internship, the student will experimentally setup an optomechanical platform consisting of a nanoparticle optically levitated in vacuum. Through a spatial modulation of the input light field, a mechanically-induced correlation between phase and amplitude fluctuations of the optical field will be enforced. Such a correlation will be maximized to achieve a quantum squeezing of the scattered light field. A funding is available to continue and expand this internship through a PhD.
Contact
Nicolas Bachelard
Laboratory : Laboratoire Ondes et Matière d'Aquitaine - UMR 5798
Team : Nanophotonics Group
Team Website
Team : Nanophotonics Group
Team Website
20/10/2023
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Thesis :
Funding :
83
Quantum chaos & non-Euclidean photonics
Domaines
Quantum optics/Atomic physics/Laser
Relativity/Astrophysics/Cosmology
Non-relativistic quantum field theory, quantum optics, complex quantum systems
Type of internship
Expérimental et théorique Description
Quantum chaos is a research field dedicated to the relationship between a quantum system and its classical counterpart. The predictions are investigated in any wave system, namely quantum, acoustic, microwaves, optics,… Recently, we demonstrated the fabrication of surface-like microlasers by Direct Laser Writing (DLW). The laser modes were located along periodic geodesics (a geodesic is the shortest path between two points on a surface, like the straight line in Euclidean space). It opens the way to a new domain, called Non-Euclidean Photonics. During the internship, the student will investigate microlasers based on a pseudosphere, a surface with constant negative curvature , where geodesics are unstable and the classical dynamics is chaotic.
Contact
Mélanie Lebental
20/10/2023
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Thesis :
Funding :
84
Femtosecond two-dimensional infrared spectroscopy in carbon dioxide and hemoglobin
Domaines
Quantum optics/Atomic physics/Laser
Biophysics
Non-linear optics
Type of internship
Expérimental Description
Two-dimensional infrared (2DIR) spectroscopy is a nonlinear optical method consisting in measuring a pump-probe spectrum which is frequency resolved in both pump and probe dimensions. It is sensitive to the coupling between vibrational modes of molecular systems and also to protein structure fluctuations. In collaboration with Laboratoire Charles Fabry (IOGS) and the Amplitude company, LOB has recently developed a new 2DIR spectrometer of unprecedented spectral resolution, thanks to a nonlinear optical method coined Chirped Pulse Upconversion allowing direct detection of MIR radiation with a visible CMOS camera. The proposed internship will consist in applying this new experiment to recording 2DIR spectra in carboxyhemoglobin and in carbon dioxide. In the latter case, the 2DIR spectrum will exhibit a large number of narrow lines associated to different rotational modes, thus evidencing the remarkable spectral resolution that can be achieved in both pump and probe dimensions. The experimental results will be compared with a numerical calculation based on a quantized rigid rotator model for calculating the 2D rovibrational spectrum.
Contact
Manuel Joffre
20/10/2023
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Thesis :
Funding :
85
Physics-based statistical models of protein sequences
Domaines
Statistical physics
Biophysics
Physics of living systems
Type of internship
Théorique, numérique Description
Understanding the connection between a protein's amino acid sequence and its function remains a significant challenge. Traditional biophysics approach address the 'sequence→3D structure' problem but not the 'sequence→function' problem. Recent data-driven approaches analyze protein evolution to build statistical models of this relationship. These models, rooted in statistical physics and machine learning, enable the design of new functional protein sequences. A current challenge is imbuing physical interpretability into these models, to understand how sequences correspond to different physical properties of proteins, and to design proteins with specific properties. The goal of the internship is to advance these models in this direction.
Contact
Olivier Rivoire
20/10/2023
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Thesis :
Funding :
86
Numerical simulations of pSHG microscopy in cornea.
Domaines
Biophysics
Physics of living systems
Non-linear optics
Type of internship
Théorique, numérique Description
Multiphoton microscopy has revolutionized 3D imaging of biological tissues over the past 10 years. Notably, second harmonic generation (SHG) microscopy enables imaging of collagen without any labelling and with unequalled sensitivity in intact tissues. This is directly related to the property of SHG to be nonzero only in dense and non-centrosymmetrical materials. Nevertheless, the build-up of SHG is a complex issue because of its coherent nonlinear nature and of the heterogeneity of collagen distribution in tissues. Collagen is indeed organized as fibrils, which size and 3D organization is specific to each tissue (skin, artery, lung, bone…). Extracting as much information as possible about the structure of a tissue from SHG images is therefore an active research field. An effective method consists in varying the excitation polarization, which yields the collagen orientation in every pixel. Nevertheless, numerical simulations are needed to model this polarimetric SHG signal for realistic tissue geometries and reconstruct in a reliable way the collagen distribution at sub-micrometer scale.
Contact
Marie-Claire Schanne-Klein
20/10/2023
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Thesis :
Funding :
87
Nanoscale Patterns and Dynamics of Evaporation/Condensation of Salty Water
Domaines
Condensed matter
Statistical physics
Soft matter
Physics of liquids
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Kinetic theory ; Diffusion ; Long-range interacting systems
Hydrodynamics/Turbulence/Fluid mechanics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental et théorique Description
Salty water is everywhere (oceans, underground, and even in the atmosphere). The way it reacts to humidity changes is important in many natural, societal and technological contexts (water harvesting, cultural heritage preservation, geophysics, civil engineering, aerosol and cloud formation, energy conversion, etc.). We follow parallel research investigations (with experiments, theory and/or numerical simulations) to elucidate how surfaces, nanoscale confinement and disorder, which can be found in many of these contexts, dictate the dynamics and patterns that emerge from transport and/or phase change of salt solutions.
Contact
Olivier Vincent
19/10/2023
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Thesis :
Funding :
88
Trees drying from the inside: physics of bubble propagation
Domaines
Condensed matter
Statistical physics
Biophysics
Soft matter
Physics of liquids
Nonequilibrium statistical physics
Physics of living systems
Non-equilibrium Statistical Physics
Hydrodynamics/Turbulence/Fluid mechanics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental et théorique Description
Numerical simulations and/or experimental investigations of patterns and dynamics related to bubble nucleation, growth and propagation in complex vascular networks inspired by trees. The general context is understanding how trees (plants in general) respond to humidity changes, and in particular drought events that are becoming more frequent. This remains a topic in physics, with external collaboration with plant physiologists.
Contact
Olivier Vincent
19/10/2023
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Thesis :
Funding :
89
Computational fluorescence microscopy
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Statistical physics
Biophysics
Soft matter
Physics of living systems
Quantum information theory and quantum technologies
Quantum optics
Non-linear optics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental et théorique Contact
Hilton Barbosa de Aguiar
19/10/2023
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Thesis :
Funding :
90
Super-resolution coherent Raman microspectroscopy
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Statistical physics
Biophysics
Soft matter
Physics of living systems
Quantum information theory and quantum technologies
Quantum optics
Non-linear optics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental et théorique Contact
Hilton Barbosa de Aguiar
19/10/2023
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Thesis :
Funding :
91
Time-domain in compressive Raman microspectroscopy
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Biophysics
Soft matter
Physics of living systems
Quantum optics
Non-linear optics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental et théorique Contact
Hilton Barbosa de Aguiar
19/10/2023
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Thesis :
Funding :
92
Etude de la dégradation microbienne de plastique
Domaines
Biophysics
Soft matter
Physics of liquids
Physics of living systems
Type of internship
Expérimental Description
La pollution plastique constitue l’un des enjeux sociétaux majeurs impactant l'environnement
et la santé. Depuis une vingtaine d’années, de nombreuses recherches pluridisciplinaires visent
à lutter contre ce fléau ainsi qu’à développer de nouveaux matériaux facilement dégradables ou
réutilisables. Nous souhaitons nous intéresser à la biodégradation, c’est à dire à la dégradation
induite par les bactéries.
Contact
Eric Raspaud
19/10/2023
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Thesis :
Funding :
93
Dynamique et statistique de lancers de dés 2d
Domaines
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Type of internship
Expérimental Description
[Français] La dynamique d’un dé (ou de n’importe quel polyèdre) tombant sur une surface est constitué d’une alternance
complexe de mouvements réguliers et de chocs dissipatifs, dont il est difficile de dégager des propriétés moyennes.
En particulier si les faces du dé ont des aires différentes, la répartition statistique des configurations finales n’est
à l’heure actuelle pas comprise.
L’objectif de ce stage de recherche en laboratoire sera d’étudier la dynamique de chute d’un ‘dé’ bidimension-
nel (confiné entre deux plaques) et de faire le lien avec la répartition statistique d’un grand nombre de lancers.
Selon l'affinité de l'étudiant·e, les expériences pourront être complétées par de la modélisation et/ou une étude numérique.
[English] Although the dynamics of a die (or any polyhedron) falling onto a surface involves only basic mechanics (rigid
body, rebounds, sliding), its complex out-of-equilibrium dynamics makes predicting statistical behaviour far
from obvious. In particular, if the faces of the die have different areas, the statistical distribution of the
results obtained is not currently understood.
The aim of this laboratory research internship will be to examine the fall of a two-dimensional ‘die’ (confined
between two plates) and to make the link with the statistics of the final state. While our first aim will be to gather experimental data, interested students may well add some theoretical modeling and/or numerical simulations.
Contact
Adrian Daerr
19/10/2023
/
Thesis :
Funding :
94
Machine learning modelling of turbulent bubble breakup
Domaines
Statistical physics
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Théorique, numérique Contact
Sergio Chibbaro
18/10/2023
/
Thesis :
Funding :
95
Multiscale Dynamics in bacterial populations
Domaines
Condensed matter
Statistical physics
Biophysics
Soft matter
Physics of living systems
Non-equilibrium Statistical Physics
Type of internship
Expérimental et théorique Description
Bacteria are one the most fundamental and abundant forms of life on Earth. For human health, they represent both a threat, with the emergence of massive multi-resistance to antibiotics, and an opportunity, as the microbiota can positively influence human physiology. The bacterial strains currently studied in research laboratories are very easy to grow and maintain, making them a highly convenient experimental system for studies at both single-cell and population levels. Our lab seeks to understand how the different scales are coupled: from protein dynamics to colony organization. To do this, we use live microscopy and image analysis to capture and model the observed spatial and temporal dynamics.
Contact
Nicolas Desprat
18/10/2023
/
Thesis :
Funding :
96
Fractures in cohesive granular flows: From cohesion-tunable particles to environmental applications
Domaines
Statistical physics
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
Among the different types of avalanches, the "slab avalanches", made of dense snow, initiate by a long crack perpendicular to the slope, and then quickly propagate downhill during the flow. Difficult to predict, they are therefore especially dangerous for skiers and others. Prediction of their behavior remains difficult and relies mainly on empirical observations. To improve our understanding of this phenomenon, we need to understand the physics at the grain scale, and the cohesive forces involved. The objective of this project is to study how fractures appear in a cohesive granular material, how they evolve, and how they influence the flow back. These questions surpass the particular case of slab avalanches and apply to other examples of fractured flows such as landslides of cohesive soil, or, in a more industrial context, self-leveling concrete flow.
To address these questions, we will combine experiments and theory-based numerical simulations. We will build up an experiment using a cohesion-controlled granular material, which has been recently synthesized to focus on the formation of fractures in a thin layer of this material and then investigate the dynamics of such system using a rotating drum. A numerical study can be done according to your taste.
Contact
Anaïs ABRAMIAN
Laboratory : Institut d'Alembert -
Team : Fluides Complexes et Instabilités Hydrodynamiques
Team Website
Team : Fluides Complexes et Instabilités Hydrodynamiques
Team Website
16/10/2023
/
Thesis :
Funding :
97
Multi-scale temporal nonlinear optical response of a biased crystal
Domaines
Non-linear optics
Quantum gases
Type of internship
Expérimental Description
Merging nonlinear optics and quantum hydrodynamics, quantum fluids of light have gained great interest in the past few years. Indeed, in properly engineered experimental optical devices, photons can acquire an effective mass and be in a fully controlled effective interaction. They behave collectively as a quantum fluid, and share remarkable common features with other systems such as superfluidity and quantum turbulence. Quantum fluids of light have been investigated mainly in one and two dimensions in various photonic platforms. At INPHYNI, in the Waves in Complex Systems group, we have implemented an experimental platform which basically consists in propagating a continuous laser beam in a nonlinear biased photorefractive crystal (Strontium Barium Niobate, SBN). In such a configuration, the evolution of the transverse optical field along the propagation axis is analogous to a 2D quantum fluid evolving in time. A major challenge in the field of quantum fluids of light is to increase its dimensions. An interesting strategy is to consider ultrashort pulses rather than continuous propagation and combine both the instantaneous electronic Kerr effect with the slow photorefractive nonlinear effect.
In this context, the goal of this internship is two-fold. The first part will be to characterize the slow photorefractive response of the biased SBN crystal, the second part will be to accurately measure its instantaneous nonlinear optical response.
Contact
Claire Michel
16/10/2023
/
Thesis :
Funding :
98
Development of a cold strontium atom source
Domaines
Quantum optics/Atomic physics/Laser
Quantum information theory and quantum technologies
Quantum gases
Type of internship
Expérimental Description
The goal of the experimental internship is to design, build and test a compact high flux cold atom source for quantum simulations with strontium. The system to be build will consist of an oven, a Zeeman slower and a 2d magneto-optical trap. During this project the student will develop expertise in several essential aspects of experiments with cold atoms ranging from laser cooling, laser spectroscopy and frequency stabilization, CAD and simulations, optics as well as vacuum technology. At the end of the internship the candidate will thus have acquired basic experimental knowledge to engage into a PhD in the field of cold atoms.
Contact
Guillaume Salomon
16/10/2023
/
Thesis :
Funding :
99
Data Analysis in the Super-Kamiokande Neutrino Experiment
Domaines
High energy physics
Type of internship
Expérimental Description
Since their discovery in 1998 (Nobel Prize) we have learnt a lot about the parameters that govern neutrino oscillations, but there are still many questions remaining. Perhaps the most exciting of these is to determine whether neutrino oscillations violate charge-parity symmetry (CPV), and so could potentially explain why we live in a matter-dominated universe. This project involves the analysis of a unique set of photographs captured by a drone underwater in Super-K. Machine learning image segmentation techniques will be explored to accurately identify photosensors in each photo. Then using the photogrammetry technique, the geometry of Super-K can be measured for the first time after being filled with water. The result will be used by physics analysis through the detector Monte Carlo simulation.
Contact
Michel Gonin
15/10/2023
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Thesis :
Funding :
100
Cosmological Constraints from Lyman Alpha Forest using Hybrid Effective Field Theory
Domaines
Relativity/Astrophysics/Cosmology
Type of internship
Théorique, numérique Description
Using small scale information found in Lyman Alpha Forest data for cosmological analysis is difficult due to uncertainties in the underlying hydrodynamical physics. One possible way to include this uncertainty accurately is using perturbation theory, in particular hybrid effective field theory approaches. In this project, students will test the ability for hybrid effective field theory to capture variations in small scale physics and apply the framework to simulated and/or real data.
Contact
Michel Gonin
14/10/2023
/
Thesis :
Funding :
101
Search for non-unitarity of the PMNS matrix in the neutrino sector with T2K and Hyper-Kamiokande experiments.
Domaines
High energy physics
Relativity/Astrophysics/Cosmology
Type of internship
Expérimental et théorique Description
For the very first time, we now have the possibility of measuring the possible violation of CP symmetry in the lepton sector through the oscillation of neutrinos, and through this, of proposing the very first brick explaining the asymmetry between matter and antimatter that we observe in our current universe. In this perspective, the current T2K experiment, and the future Hyper-Kamiokande, are the experiments best placed to realize this fundamental discovery. However, the parameterization (known as PMNS) currently used in neutrino experiments limits the universality of this discovery, as well as possible physics tests beyond the standard model. This subject proposes to rewrite the neutrino oscillation algorithm used in T2K and Hyper-Kamiokande considering a non-unitarity of the PMNS matrix, then to apply the result to the data collected by T2K since 2011 for the first time. This result will constitute a first physics search beyond the standard model by this method in T2K, as well as obtaining universal results on the violation of CP symmetry.
Contact
Michel Gonin
14/10/2023
/
Thesis :
Funding :
102
Development of jet reconstruction ML algorithm for Higgs Bosons factories
Domaines
High energy physics
Type of internship
Expérimental Description
iggs factories, including ILC in Japan, are next-generation electron-positron collider projects to explore fundamental questions of the universe. One of the key characteristics of detectors for Higgs factories is highly-granular calorimetry for precise jet measurement. The "particle flow" algorithm to analysis big data from highly-granular sensors is critical for the jet reconstruction, and we are working on improvement of the algorithm using modern deep-learning techniques. The main part of this internship program is a simulation study of the algorithm, including implementing and improving track-cluster matching algorithm, investigation of effect of precise timing measurement, and investigate detector configuration giving maximal performance. Based on intention of the applicant, related hardware studies on silicon sensors and readout electronics of the highly-granular silicon calorimeter can be included
Contact
Michel Gonin
14/10/2023
/
Thesis :
Funding :
103
Physical properties of distant galaxies via Data from ALMA and James Webb Space Telescopes.
Domaines
Relativity/Astrophysics/Cosmology
Type of internship
Expérimental et théorique Description
In this topic, we will investigate the physical properties of dust-enshrouded high-redshift galaxies uncovered by recent ALMA and/or JWST observations. We will focus on spatially-resolved properties of galaxies using high-spatial resolution data and energy-balance codes to model the observed spectral energy distributions and understand the roles of cosmic dust in the early universe.
Contact
Michel Gonin
14/10/2023
/
Thesis :
Funding :
104
High Energy Gamma-Ray Astronomy (neutron stars, black holes)
Domaines
High energy physics
Relativity/Astrophysics/Cosmology
Type of internship
Expérimental Description
The proposed project is a deep follow-up study on the gamma-ray binary LS I +61 303 at GeV energies. It is one of the best studied binary systems at high energies showing a very particular behavior: On top of the orbital period of about one month, it shows a super-orbital modulation of about 4 years in several wavelengths.
Since the discovery of this phenomenon at GeV energies, the dataset taken by the satellite Fermi has doubled. We propose to analyze the latest Fermi-LAT dataset on the source, prove or falsify the findings done 10 years ago and perform a deep study on the orbital behavior of the source. These findings will be of great interest for the community.
Contact
Michel Gonin
14/10/2023
/
Thesis :
Funding :
105
Looking for radio signals from ultra-high energy cosmic particles
Domaines
High energy physics
Relativity/Astrophysics/Cosmology
Type of internship
Expérimental Description
The GRAND (Giant Radio Array for Neutrino Detection) project aims at detecting ultra-high energy messengers (atomic nuclei, neutrinos, gamma-rays) coming from the most powerful sources in the Universe, with a 200'000 radio antenna array. Two prototypes have been deployed in 2023 in desert areas in China and Argentina, and the first dataset is currently being analyzed. In this internship, the candidate(s) will take part in this exciting phase of pioneering data analysis.
Two possible axes of research will be proposed, based on the collected data at both sites or based on simulations, for a prospective study on the China prototype.
a) the identification of specific signatures in the radio signals from cosmic particles. This will be used to discriminate efficiently against the background radio noise.
b) simulations to assess the performances of a hybrid detector (radio antennas + scintillators) at the China site, to detect cosmic particles
Contact
Michel Gonin
14/10/2023
/
Thesis :
Funding :
106
Can modified gravity explain the accelerated expansion of the Universe ?
Domaines
Relativity/Astrophysics/Cosmology
Type of internship
Expérimental et théorique Description
The study of new probes for analyzing modified gravity simulations of the large-scale structure of the Universe. Modified gravity (MG) theories of the type of f(R) gravity can explain the accelerated expansion of the Universe without invoking the cosmological constant. Such models require introducing a new scalar field that naturally predicts rich gravitational effects in a different way from general relativity (GR). These modifications lead to changes in the environment of large-scale structures that could be used to distinguish this model from GR. The goal of this project is to provide critical tools to study modified gravity, and help to answer the key scientific question: Does modified gravity successfully explain the accelerated expansion of the Universe?
Contact
Michel Gonin
14/10/2023
/
Thesis :
Funding :
107
NbN thin film synthesis and characterization
Domaines
Condensed matter
Low dimension physics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
Niobium nitride (NbN) is a very interesting material both for its fundamental properties but also for applications in quantum technologies. It is a superconducting material with a relatively “high” critical temperature (up to 13 K) and the transition temperature can be tuned with the thickness of the film. All this makes it a promising candidate for a wide variety of quantum technology applications without the need for a dilution refrigerator. Recently it has been used for magnetic imaging at “high” temperature, to make high quality resonators for circuit QED, high range cryogenic thermometers and single photon detectors.
In the lab we have been developing a NbN magnetron deposition systems that will produce such superconducting films for different team in the group. Your task during this internship will be to make such high quality NbN films, to develop reliable deposition protocols and characterize the resulting films. The characterization will be electronic (transport), optical (reflectometry and ellipsometry) and also topographic (AFM). Depending on the progress made, you will be involved in the fabrication of quantum circuits made out of these films.
This internship will give you direct hands-on experience on a wide range of experimental techniques that are widely used in condensed matter and quantum technologies (ultra-high vacuum, cryogenic, DC transport, film deposition, ellipsometry, AFM).
Contact
Arthur Marguerite
12/10/2023
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Thesis :
Funding :
108
Balescu--Lenard equation and marginal stability crossing
Domaines
Kinetic theory ; Diffusion ; Long-range interacting systems
Type of internship
Théorique, numérique Description
Long-range interacting N-body systems (e.g., plasmas or stellar clusters) relax through finite-N effects, as described by the Balescu--Lenard kinetic equation. Yet, this equation diverges when the system approaches an instability. The focus of this internship is to generalise this kinetic equation to appropriately cure this divergence at marginal stability.
Contact
Jean-Baptiste Fouvry
10/10/2023
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Thesis :
Funding :
109
Impact of antibiotics on mutations in bacteria
Domaines
Biophysics
Type of internship
Expérimental Contact
Lydia Robert
10/10/2023
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Thesis :
Funding :
110
Information flow and polymer physics of gene activity
Domaines
Biophysics
Type of internship
Expérimental et théorique Description
Our project tackles the fundamental challenge of bridging the diverse temporal and spatial scales of biological development. From the nanoscale molecular interactions that occur in seconds to the formation of millimeter-to-meter-scale tissues over days, nature's complexity is staggering. This project seeks to unveil how information flows from molecular transcription factors to orchestrate tissue formation. This project employs a multidisciplinary approach, combining experimental techniques (quantitative microscopy) with theoretical modeling (polymer and statistical physics). It aims to decode the mechanisms governing the interplay between cellular regulation and tissue development. This research has broad implications for biophysics, developmental biology, and regenerative medicine.
Contact
Thomas Gregor
10/10/2023
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Thesis :
Funding :
111
How to maintain the two essential functions of insects in a changing climate? Microrheology and chemistry of cuticular hydrocarbons in ants
Domaines
Biophysics
Type of internship
Expérimental Description
In this project, we will study the relationship between the rheology and chemical composition of cuticular hydrocarbons in ants, under acclimatisation conditions. This exciting project, which spans physics, chemistry and biology, takes place at Laboratoire Matière et Systèmes Complexes (MSC), located in Paris 13e. It will be carried out in international and interdisciplinary collaboration with the Institute of Organic and Molecular Evolution. A short-term internship at the University of Mainz (Germany), for chemical and behavioural analyses, is possible.
Contact
Berengere ABOU
09/10/2023
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Thesis :
Funding :
112
Growth and spintronics of low symmetry magnetic layers
Domaines
Condensed matter
Type of internship
Expérimental et théorique Description
The goal of this internship is to realize ultrathin films of metallic and magnetic layers on insulating substrates of very low symmetry. The samples will be made in the clean room of the Matériaux et Phénomènes Quantiques lab in Paris and characterized by x-ray diffraction and vibrating sample magnetometry or magneto-optical effects for their magnetic properties. The second part of the internship will be to achieve lithography and electronic transport measurements on those samples for magnetic memory applications. This part will be done in part in Singapore, in collaboration with Pr. Yang's group, at the Computer and Electrical Engineering departement of the National University of Singapore.
Contact
Vincent Repain
09/10/2023
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Thesis :
Funding :
113
Intracellular Nanorheology with molecular rotors; Application to red blood cell pathologies
Domaines
Biophysics
Type of internship
Expérimental et théorique Description
Join our research project at the interface of physics, biology and clinical practice, studying pathologies that affect the deformability of red blood cells.
Contact
Berengere ABOU
09/10/2023
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Thesis :
Funding :