To find the right proposal !
Internship and thesis proposals
Criteria for selection
Number of proposals
106
1
Mixing of a stable strati cation by a planetary collision
Domaines
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
The Earth formed 4.5 billion years ago by high-energy collisions between planetary embryos. Each Earth-forming impact induced shock waves that melted the colliding embryos, bringing these events into the realm of fluid mechanics (Landeau et al. 2021, Maller et al. 2024). The student will use laboratory experiments (figure 1) to investigate the dynamics of these giant planetary collisions.
Current models of planetary accretion suggest that the core and the mantle of the Earth were stratified in composition after their formation. Whether the last impact that formed the Earth and its Moon mixed and homogenized this stratification remains debated. This question is critical for the origin of the primordial heterogeneities in Earth's mantle that are inferred from geochemical observations.
The successful candidate will conduct experiments on the impact of a liquid volume into a pool of a linearly stratified liquid (figure 2). They will record the flow on a high-speed camera and characterize the turbulent mixing using laser-induced fluorescence and conductivity probes. Using scripts in Python, the student will estimate the mixing efficiency as a function of the ratio of the stratification strength to the impact speed. These results will provide key constraints on the primordial stratification of Earth's mantle.
Contact
Maylis Landeau
18/11/2024
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Thesis :
Funding :
2
Magnetotactic Bacteria in Porous Media & Active Matter Anderson Localization
Domaines
Statistical physics
Biophysics
Soft matter
Nonequilibrium statistical physics
Physics of living systems
Non-equilibrium Statistical Physics
Type of internship
Théorique, numérique Description
Magnetotactic bacteria are microorganisms that orient and navigate along the Earth's magnetic field lines, using chains of magnetic nanoparticles embedded in their membranes. These bacteria play an important role in marine ecology and have potential applications in targeted drug delivery. However, their motility and transport in complex porous environments, such as soils or the human vascular network, remain poorly understood.
Magnetotactic bacteria have been shown to move collectively as a soliton, i.e., a freely propagating density wave. Yet, these bacteria mostly occupy the seabed, a densely confined and disordered porous medium. Within such disordered media, we expect the onset of arrested phase, similar to Anderson's localization, whereby the disorder leads to a spatial confinement of waves.
In the M2 and PhD, we aim to understand the critical level of disorder that triggers a localization transition, using tools from active matter & statistical physics, including an active phase field model.
Please also note that:
(1) We will work in close collaboration with the group of N. Waisbord, an physicist who is also expert in theoretical modelling.
(2) We do not require any previous experience in biology.
(3) We are based on the Marseille Luminy, which is arguably the most beautiful campus in the world, located right in the middle of the Calanques National Park.
Contact
Jean-François Rupprecht
17/11/2024
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Thesis :
Funding :
3
Theory of active phase separation in cell assemblies; analysis & modelling
Domaines
Statistical physics
Biophysics
Soft matter
Nonequilibrium statistical physics
Physics of living systems
Non-equilibrium Statistical Physics
Type of internship
Théorique, numérique Description
Embryonic development is a complex hydrodynamic problem. Global flows stem from individual cell-cell rearrangements, which can either resist or drive embryonic flows. Tracking their location and orientation is crucial to understanding morphogenesis, yet it remains a computationally challenging task. Here, in this M1/M2 internship, we propose to adapt a method that we have proven works for detecting cell divisions. This will be the starting point for a theoretical PhD. Indeed, preliminary results in our group support that modulation in the rates of cell-cell rearrangements triggers phase separation between cell types, but we seek to develop simplified analytical models to account for this effect.
Please also note that:
(1) We have M2 and PhD internship openings in our group to explore this subject, but we could also recruit a motivated M1 student.
(2) We will work in close collaboration with the groups of Sham Tlili, Virgile Viasnoff, Pierre-François Leone & Thomas Lecuit.
(3) We do not require any previous experience in deep learning nor in biology ; this subject will be an opportunity to learn tools such as CNN or GAN, and I have an experience in supervising physics students on these subjects; the project is interdisciplinary, but addresses physics questions;
(4) Marseille Luminy is arguably the most beautiful campus in the world, right in the middle of the Calanques National Parc.
Contact
Jean-François Rupprecht
17/11/2024
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Thesis :
Funding :
4
Rare-earth-doped crystal spectroscopy for signal processing architectures
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Quantum information theory and quantum technologies
Type of internship
Expérimental Description
Rare-earth ion-doped crystals exhibit exceptionally narrow optical transitions at low temperatures (around 3K). These unique properties make them ideal for foundational quantum technology applications, including quantum memories, quantum sensors, and quantum-enabled signal processing architectures. Over the past decades, our team, in a long-standing collaboration with Thales Research & Technology and IRCP, has developed a number of state-of-the-art signal processing designs, including a spectral analyzer demonstrator at the industrial level and an agile photonic filter. Nevertheless, the development of cutting-edge architectures goes hand-in-hand with ongoing exploration of alternative materials, always with specific applications in mind. With this internship, we want to continue our exploration focusing on Tm:YGG and Er:YSO, in the perspective of optimizing our spectrum analyzer designs.
Contact
Anne Louchet-Chauvet
Laboratory : Institut Langevin - Ondes et Images - UMR7587
Team : Materials, Resonances, Interfaces
Team Website
Team : Materials, Resonances, Interfaces
Team Website
13/11/2024
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Thesis :
Funding :
5
Air film dynamics
Domaines
Condensed matter
Biophysics
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Théorique, numérique Description
Air film dynamics -
Context: Gas transfer at the ocean surface has a critical importance for climate, as it captures around 30% of the CO2 released into the atmosphere, and for marine biological activity, as it provides the necessary O2. This transfer can be promoted by the entrapment of bubbles, produced through impacting rain drops or breaking waves. The shape and dynamics of the bubbles are important to model these transfers.
Goals: We propose in this project to study the contraction dynamics of an air film into a fluid. We will systematically vary the gas and fluid properties in different geometries to understand their contraction velocity and rupture mechanisms. This project will combine numerical simulations (using the open-source code Basilisk) with theoretical analysis to uncover the physical processes involved in the gas transfer into the ocean.
Profile: Candidates should have a good training in Fluid Mechanics and Computational Fluid Dynamics.
Environment: The project will take place in the laboratory of Prof. Marie-Jean THORAVAL at LadHyX in École Polytechnique, in the South of Paris.
Contact
Marie-Jean THORAVAL
12/11/2024
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Thesis :
Funding :
6
Impact of compound drops: Bouncing or Sticky?
Domaines
Condensed matter
Biophysics
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
Impact of compound drops: Bouncing or Sticky? -
Context: The impact of a drop onto a solid or liquid surface has a wide range of applications including combustion, 3D printing, biological microarrays, pharmaceutics and the food industry. While most of them rely on single fluid drops, the emergence of new additive manufacturing techniques promises to revolutionize these industries by combining multiple fluids into compound drops. One of the critical challenges in these applications is to control the deposition process of the impacting drop and therefore its spreading, potential rebound and splashing.
Goals: We propose in this project to control the rebound of the water core by varying the viscosity and thickness of the outer oil layer. We will combine high-speed imaging experiments with high resolution numerical simulations (using the open-source code Basilisk) to investigate these complex dynamics, and uncover the physical processes involved in the deposition of compound drops.
Profile: Candidates should have a good training in Fluid Mechanics. The project can either be focused on experimental observations and/or numerical simulations depending on the applicant.
Environment: The project will take place in the laboratory of Professor Marie-Jean THORAVAL at LadHyX in École Polytechnique, in the South of Paris.
Contact
Marie-Jean THORAVAL
12/11/2024
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Thesis :
Funding :
7
Drop impact on a pool of immiscible liquid
Domaines
Condensed matter
Biophysics
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Théorique, numérique Description
Drop impact on a pool of immiscible liquid
Context: The impact of a liquid drop onto a liquid surface is a commonly observed phenomenon in nature and throughout daily life, and is important for many industrial processes such as spray painting, inkjet printing and spreading of pesticides. It has been demonstrated recently that this process could be used for the mass production of particles with complex shapes and cell encapsulation [1]. The geometry of the resulting particles strongly depends on the impact dynamics and the deformation of the interfaces.
Goals: In this project, we propose to investigate the formation of complex encapsulations formed by the impact of a liquid drop on a pool of immiscible liquid. We will systematically study the impact of water drops on a pool of an immiscible liquid such as silicone oil. We will combine high-speed imaging experiments with high resolution numerical simulations (using the open-source code Basilisk) to investigate these complex dynamics, and uncover the physical processes involved.
Profile: Candidates should have a good training in Fluid Mechanics. The project can either be focused on experimental observations and/or numerical simulations depending on the applicant.
Environment: The project will take place in the laboratory of Prof. Marie-Jean THORAVAL at LadHyX in École Polytechnique, in the South of Paris.
Contact
Marie-Jean THORAVAL
12/11/2024
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Thesis :
Funding :
8
Sedimentation of diatom chain colonies
Domaines
Biophysics
Soft matter
Physics of liquids
Physics of living systems
Type of internship
Théorique, numérique Description
Diatom chains are cohesive assemblies of unicellular microorganisms that are found in still and fresh waters. Some species are passively transported by ambient currents and settle due to the weight of their dense silica shells, while others have use various strategies to move or self-propel. One species in particular, called Bacillaria Paxillifer, forms colonies of stacked rectangular cells that slide along each other while remaining parallel. As observed in experiments, and reproduced by our numerical model, their intriguing coordinated motion, leads to beautiful and nontrivial trajectories at the scale of the colony. However, the effect of gravity and external flows on the dynamics of diatom chains must be investigated to understand the behavior of plankton and marine snow aggregates as they sink, and capture CO2, to the ocean depths...
Contact
Blaise Delmotte
12/11/2024
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Thesis :
Funding :
9
Hydrogen storage in clay materials
Domaines
Condensed matter
Quantum gases
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Contact
Pascale Launois
Laboratory : Laboratoire de Physique des Solides - UMR8502
Team : Matière et Rayonnement
Team Website
Team : Matière et Rayonnement
Team Website
11/11/2024
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Thesis :
Funding :
10
Quantum consistency of string interactions
Domaines
Fields theory/String theory
Type of internship
Théorique, numérique Description
In this M1 internship, the intern will revisit a problem as old as string theory itself: the quantum mechanical consistency of interactions between fundamental strings. More precisely, the intern will study the quantum mechanical scattering amplitude at the first order in perturbation theory. It is famously given by the Veneziano formula, derived in the 60s.
While it has been known since the 70s that String Theory is consistent quantum mechanically, it has never been shown directly that the Veneziano formula respects a unitary evolution. Recently, it has been observed empirically that the Veneziano formula obeys a remarkable property, stronger than unitarity [1]. The intern will work on a mathematical proof of this property.
In practice, this will amount to literally looking at the properties of the poles of the Euler beta function. As surprising as it may sound, more than 2 centuries after Euler, there are still simple things to understand about this object which can in addition tell us something new about string theory.
[1] Eckner, Figueroa, Tourkine 2024, https://arxiv.org/abs/2401.08736
Contact
Piotr Tourkine
07/11/2024
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Thesis :
Funding :
11
Quantum dot fluorescence and optomechanical coupling
Domaines
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
The emission of colloidal quantum dots is highly dependent on their environment. Placed between two layers of gold, and excited in UV light, their emission couples with surface plasmons and its dynamics is accelerated. The smaller the gap between the two gold layers, the more the emission is modified. We propose to actively modify the spacing between the two layers in order to modify quantum dot emission.
We will use the transient grating method, which involves exciting the sample with two infrared laser beams (exc =1064nm; 30ps pulse duration) to produce interference bangs with a period . Through photoelasticity, the standing waves thus created cause the sample to vibrate, modulating its thickness.
The aim of the internship will be to study how the acoustic wave thus created modifies the properties of the light emitted.
The first step will be to produce the samples. After depositing an optically thick layer of gold on a glass subtrate, a solution of CdSe/CdS quantum dots will be deposited. This emitter layer is then covered by a thin layer of gold. Secondly, this layer will be optically characterized under a microscope, both to characterize its thickness in white light and the fluorescence of the quantum dots under UV illumination. Finally, we'll use the transient grating method to change the thickness of the sample. Both thickness and quantum dot fluorescence will be studied.
Contact
Agnes MAITRE
07/11/2024
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Thesis :
Funding :
12
Temperature-controlled plasmonic nano-antennas
Domaines
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
Already around 15 years ago, it has been shown that liquid crystal topological defects can be used to confine and organize nanoparticles. In particular, oriented chains of nanospheres or of tip-to-tip nanorods have been formed in unidimensional smectic defects, dislocations and disclinations (Fig.1) [1]. The liquid crystal phase transitions occurring at low temperature, liquid crystals can provide temperature-activated assemblies of nanoparticles [2]. In this context, we propose to use oriented unidimensional smectic defects in order to build plasmonic nanoantennas based on strictly facing gold nanorods in close contact. We will study the evolution of the light absorption of the nanoantennas when temperature is increased in relation with the disappearing of the liquid crystal defects driven by the liquid crystal phase transition. This study will pave the way for an activation of the coupling strength between nanoparticles actively tuned by the temperature. This would be a first step towards future optical devices based on visual appearance controlled by varying temperature.
[1] S.P. Do et al. Nano Letters 20 (2020) 1598, [2] H. Jeridi, Appl. Phys. Lett. 123 (2023) 203101
Contact
Emmanuelle Lacaze
Laboratory : Institut des NanoSciences de Paris - UMR 7588
Team : Chemical Physics and Dynamics of Surfaces
Team Website
Team : Chemical Physics and Dynamics of Surfaces
Team Website
06/11/2024
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Thesis :
Funding :
13
Understanding the causes of uterine hypercontractility in endometriosis
Domaines
Biophysics
Physics of living systems
Type of internship
Expérimental et théorique Description
Endometriosis is a pathology affecting 6-10% of the female population, characterized by the implantation of uterine endometrial nodules either in the body of the uterus (known as adenomyosis) or ectopically, on various organs in contact with the peritoneal cavity such as the bladder, intestines, Fallopian tubes etc. This pathology results in severe pain during menstruation and can lead to infertility. Endometriosis and adenomyosis are associated with hypercontractility of the myometrium, the uterine smooth muscle. The cause of hypercontractility in endometriosis is currently not known, and could be a major player in disease pathogenesis, treatment and prevention. The goal of our project is to understand whether hypercontractility can result from a structural alteration of the architecture of the uterine wall, for example of the smooth muscle, of its innervation, or its hormone receptor distribution. This internship focuses on the quantitative analysis of histological images of the uterine muscle by machine learning techniques.
Contact
Nicolas Chevalier
Laboratory : MSC - UMR7057
Team : Morphogenèse et Dynamique des Systèmes Auto-Organisés
Team Website
Team : Morphogenèse et Dynamique des Systèmes Auto-Organisés
Team Website
06/11/2024
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Thesis :
Funding :
14
Thermal avalanches and depinning transition of a contact line
Domaines
Statistical physics
Physics of liquids
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
Thermal avalanches serve as a unifying mechanism for heterogeneous flows in disordered materials and glassy systems. The dynamical heterogeneities in these materials, which reflect the interplay between endogenous mechanical noise and exogenous thermal noise, have primarily been studied theoretically in the context of creep flows of pinned elastic manifolds and in simulations of super-cooled liquids, with the notable exception of the logarithmic aging of crumpled sheets. The aim of the internship and the PhD thesis is to investigate the effect of finite temperature on the depinning transition of a contact line, utilizing a combination of controlled laboratory experiments, theoretical analysis, and numerical simulations.
Contact
Kristina Davitt
06/11/2024
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Thesis :
Funding :
15
Eigenvector Continuation in Nuclear Ab Initio Methods
Domaines
Nuclear physics and Nuclear astrophysics
Type of internship
Théorique, numérique Description
Eigenvector Continuation (EC) is based on the idea of leveraging the information contained in a small number of known solutions (eigenvectors) of a system's Hamiltonian to predict the solutions in a broader parameter space. This approach is especially useful when dealing with systems where exact solutions are difficult or computationally expensive to obtain. In this project, we will apply EC to ab initio nuclear many-body calculations using the no-core shell model with continuum (NCSMC) approach, which aims to predict nuclear structure and reactions directly from fundamental forces and provide a unified treatment of a wide range of nuclear phenomena (bound and unbound states, scattering and reaction observables). EC can significantly reduce the computational cost by narrowing down the necessary subspace for solving the many-body Schrödinger equation. Additionally, EC provides an efficient framework for exploring the effects of varying parameters, thereby improving the accuracy of uncertainty estimates in nuclear theory predictions.
Contact
Guillaume Hupin
06/11/2024
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Thesis :
Funding :
16
Cloud patterns, convective self-aggregation and global warming
Domaines
Physics of liquids
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
The aim of the internship and the PhD thesis is to investigate the effect of entrainment, preconditioning and convective self-aggregation on cloud patterns, in connection to global warming issues, using a combination of field analysis, controlled laboratory experiments, theory and numerical simulations.
Objectives — To address the organization of convection and the formation of cloud patterns, the proposal starts with two central questions. How does convection self-organize when an unstable turbulent layer is capped by a stably stratified layer? What controls the survival time against evaporation and the buoyant ascent dynamics of active clouds? The second problem requires a detailed understanding of the heterogeneities of turbulent mixing around the fractal edges of clouds in the ascending phase, i.e., the entrainment of the external fluid and thus humidity, cold, and nuclei. The environment of the clouds plays a key role in their ascending dynamics generated by the latent heat released during the nucleation of droplets. Its structure arises from two concurrent processes: long-term pre-conditioning, linked to radiative effects and overturning circulation, and the modification of thermofluidic fields by active clouds that stop their ascent and evaporate, releasing their thermal energy, nuclei, and humidity. We thus hypothesize that this local memory of previous clouds plays a key role in understanding cloud patterns as an effective spatio-temporal interaction.
Contact
Bruno Andreotti
05/11/2024
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Thesis :
Funding :
17
Time- and space-resolved detection of GHz magnetization dynamics
Domaines
Condensed matter
Type of internship
Expérimental Description
In computers magnetism intervenes in the data storage components, with information coded by the magnetization direction of submicronic magnetic domains. The calculations are instead done using semiconducting materials, with transistors performing logical operations (“NOT”, “AND” etc.). A whole new paradigm proposes to use magnetic materials to perform these operations, by encoding the information on the amplitude and phase of so-called “spin-waves”, magnetic excitations. They can be excited by RF antennas, or more recently by surface acoustic waves, thanks to magneto-elasticity (an effect coupling magnetization and strain ). Foreseen advantages are a higher integrability, a higher tunability and even a lower consumption of devices for our increasingly energy-greedy digital world.
Most groups detect these spin waves electrically, after propagation along a wave-guide, or a delay line. While these measurements are ideal for a commercial device, they do not provide information about the physics at play between the excitation and detection of the waves. The aim of this internship will therefore be to improve an existing set-up capable of synchronizing an RF excitation with short laser pulses probing the magnetization dynamics induced by the resulting GHz RF field or strain wave. The challenge will be to improve the signal to noise ratio, and increase the maximum (minimum) spin wave detectable frequency (wave-length).
Contact
Laura Thevenard
05/11/2024
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Thesis :
Funding :
18
Developing charge-tunable coupled quantum dot devices for quantum computation
Domaines
Condensed matter
Quantum information theory and quantum technologies
Quantum optics
Type of internship
Expérimental Description
In this internship we will fabricate coupled quantum dots, where the two dots are close enough that carriers can tunnel coherently between them. We will do this using molecular beam epitaxy, a thin-film growth technique, which allows precise control of layer thicknesses and composition. These dots will be embedded in diode structures allowing a field to applied across the dots, bringing their energy levels into resonance to create delocalised electronic states. The student will have the opportunity to participate in all the stages of development of a new
quantum device: from device design, thin film growth and device fabrication to the low
temperature photoluminescence measurements of quantum confinement effects.
Contact
Paola Atkinson
04/11/2024
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Thesis :
Funding :
19
Tuning the properties of a 2D superconductor by epitaxial growth
Domaines
Condensed matter
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
During this internship we will study the molecular beam epitaxial (MBE) growth of the superconducting transition metal dichalcogenide NbSe2. One of the challenges in MBE growth of layered materials is the lack of direct bonding between the substrate and the growing layer. This leads to variablity in the in-plane alignment of the islands that form in the initial stages of growth, resulting in a polycrystalline thin film after island coalescence and a disordered layer stacking in multi-layer films. Here we will use both X-ray diffraction and low-temperature transport measurements to study the effect of different heterostructure designs on the crystalline and superconducting properties of NbSe2 thin films.
Contact
Paola Atkinson
04/11/2024
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Thesis :
Funding :
20
Predicting the band gap of a non-toxic metal halide perovskite for solar cell applications
Domaines
Condensed matter
Type of internship
Théorique, numérique Description
Inorganic metal halide perovskites are promising materials for future efficient and low-cost solar cells. The band gap of these materials depends on the composition and one of the most interesting candidates is cesium lead iodide that combines good electronic properties (e.g. band gap of 1.7 eV) with improved stability. The drawback is that lead is toxic, and, hence, it is desirable to replace it with an element like tin. In this project, we will investigate the influence of this substitution on the electronic structure. The band gap is expected to reduce, and, similarly to the lead-based materials, various phase transitions occur as a function of temperature. While experiments show a weak variation of the band gap across the phase transitions, ab initio calculations predict a gap variation as large as 0.5 eV. The difference is expected to originate from thermal fluctuations (not taken into account in standard band gap calculations), but a complete understanding is missing. Taking into account many-body effects and spin-orbit coupling we will determine the band structure of the high- and low-temperature phases and analyse the origin of the discrepancies. We will also investigate whether it is possible to induce a topological transition by applying hydrostatic pressure.
Contact
Maria Hellgren
03/11/2024
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Thesis :
Funding :
21
Improving stochastic simulations of complex chemical systems with bitwise arithmetic
Domaines
Statistical physics
Biophysics
Physics of living systems
Type of internship
Théorique, numérique Description
The Gillespie algorithm is a powerful computational tool to simulate the dynamics of a system of interacting chemical species in regimes where particle numbers are small, and stochastic fluctuations are large. This well-known algorithm becomes computationally demanding when one attempts to sample a large number of configurations, e.g. looking for rare samples in the dynamics, or simulating a large number of species or reactions. We propose to develop a new method to increase the computational yield of the algorithm, by leveraging the boolean representation of particle numbers as they are stored in a computer.
Different applications of the algorithm will be explored in the context of simulating complex chemical systems, which are typically non-well mixed and contains a large number of species and reactions.
The student will be tasked with the numerical implementation of this parallel Gillespie algorithm, and with its application to a few representative models of interacting chemical species.
The student will acquire valuable interdisciplinary skills, such as proficiency in C++, and getting familiar with models of chemical-reaction networks.
Contact
Michele Castellana
Laboratory : PCC, Institut Curie - UMR168
Team : Dynamic Control of Signaling and Gene Expression
Team Website
Team : Dynamic Control of Signaling and Gene Expression
Team Website
02/11/2024
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Thesis :
Funding :
22
Looking for potential variations of the proton-to-electron mass ratio and other tests of fundamental physics via precision measurements with molecules
Domaines
Quantum optics/Atomic physics/Laser
Relativity/Astrophysics/Cosmology
Quantum information theory and quantum technologies
Non-linear optics
Metrology
Type of internship
Expérimental Description
The master student will participate in cutting-edge experiments aimed at ultra-precise measurements of rovibrational molecular transitions and dedicated to measuring/constraining the potential time variation of the proton-to-electron mass ratio (µ), a fundamental constant of the standard model (SM). Such variations, if detected, would be a signature of physics beyond the SM, providing insights into the nature of dark matter and dark energy. The idea here is to compare molecular spectra of cosmic objects with corresponding laboratory data. The experimental setup is based on quantum cascade lasers (QCLs) locked to optical frequency combs, with traceability to primary frequency standards, a breakthrough technology at the forefront of frequenccy metrology developed at Laboratoire de Physique des Lasers (LPL), allowing unprecedented spectroscopic precision in the mid-infrared range.
Contact
Benoît Darquié
02/11/2024
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Thesis :
Funding :
23
Exploring planetary interiors with shock-compression experiments
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Physics of liquids
Nouveaux états électroniques de la matière corrélée
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
At LULI we can use laser-based shock compression techniques to study physical properties of material
relevant for planetary science. In particular we are interested equations of state (EOS), chemical
and transport properties of iron-bearing silicates and planetary ices (i.e. H2O/CH4/NH3 systems).
These data will contribute to improve interior models of terrestrial-like planets, including super-
Earths, as well as icy giants, such as Uranus and Neptune and the numerous Neptune-like
exoplanets recently discovered.
The internship offers the possibility to learn the foundations of the experiments on large laser
facilities. Upon availability, you will have the possibility to participate to new experiments. At the
same time, you will learn and actively participate to the data analysis of recent experiments. You
will be in charge of the analysis of the optical data, such as velocity interferometry and self-
emission for pressure and temperature estimation. The analysis also includes some auxiliary
experiments for the measurement of ancillary quantities, such as the refractive index under
pressure. During the internship, you will have the opportunity to discuss the results you will obtain
in the context of international collaborations, including experts in planetary modeling and ab initio
calculations.
Contact
Mandy Bethkenhagen
31/10/2024
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Thesis :
Funding :
24
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
Type of internship
Théorique, numérique Description
The interiors of ice giant planets such as Uranus and Neptune are dominated by water-rich molecular mixtures at high temperatures and pressures. Current interior models aiming at modeling the planets’ composition in agreement with observations assume a three-layer structure and simplify the complex mixture by using water as surrogate. The internship offers the possibility to 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 C-H-O mixtures 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
31/10/2024
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Thesis :
Funding :
25
Experimental Molecular Dynamics - Watching individual liquid molecules moving at interfaces
Domaines
Condensed matter
Statistical physics
Biophysics
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
What if we could directly watch how single liquid molecules move close to a solid surfaces? While molecular-scale dynamics at interfaces play a key role in a variety of processes in soft matter (from wetting, tribology, down to confined flow in nanofluidic devices), direct access to these interfacial transport processes at the molecular scale has remained a distant experimental goal. We propose in this internship to bridge this gap by exploring the used of state-of-the-art single-molecule and super-resolution fluorescence microscopy technique, to directly visualize and track molecular motion in dense polymeric liquid melts at the nanoscale, an ability which has been so far exclusive to molecular dynamic simulations!
Contact
Jean Comtet
30/10/2024
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Thesis :
Funding :
26
Watching interfacial charge dynamics following liquid and solid triboelectrification
Domaines
Condensed matter
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
Triboelectric charging - the process by which dielectric surfaces can acquire a net charge when rubbed together - represents a fundamentally misunderstood process in physics, with both fundamental and mundane consequences. The idea of this internship is to focus on the particular case of liquid triboelectrification, whereby water drops sliding on hydrophobic surfaces leads to a macroscopic separation of charges. In particular, we will employ recently developped surface charge mapping strategies to probe the peculiar dynamics of the ions trapped at the solid/gaz interface following liquid tribocharging.
Contact
Jean Comtet
30/10/2024
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Thesis :
Funding :
27
Perturbative QCD & Quarkonia: radiative corrections
Domaines
High energy physics
Fields theory/String theory
Type of internship
Théorique, numérique Description
The goal of the internship will be to understand techniques and concepts of Next-To-Leading Order (NLO) calculations, which involves computing both virtual 1-loop and real radiation diagrams. Individual contributions will exhibit different type of singularities in the dimensional regulator. The student will learn these concepts and also aspects related to renormalisation and factorisation in the framework of quarkonium production. Charmonium and bottomonium production, bound states consisting of a heavy quark and its anti-quark, cc and bb pairs respectively, provide interesting opportunities to study the interplay between the perturbative and non-perturbative regimes of Quantum Chromodynamics (QCD) which is at the heart of formation of hadrons such as the proton. See for more details the description in the PDF file and references therein.
Contact
Melih OZCELIK
30/10/2024
/
Thesis :
Funding :
28
Tissue compaction and shape emergence during chicken axial morphogenesis
Domaines
Biophysics
Type of internship
Expérimental Description
We are looking for a motivated student willing to join our team to work on an experimental biophysics project where we study the physics of morphogenesis during embryonic body axis development. We investigate the role of mechanics and the cross talk between mechanics and biochemistry in embryonic tissue patterning and emergence of shapes in the context of Active Soft Matter Physics. To understand the minimal physical elements necessary for shape emergence in embryonic tissues, we will setup an in vitro approach mimicking the living conditions and combine micromanipulation techniques, microscopy and image analysis for quantifying the tissue behaviour in various mechanical and chemical conditions.
Please see the pdf file for more detail.
Contact
Karine Guevorkian
Laboratory : CCF, Institut Curie -
Team : Dynamic Control of Signaling and Gene Expression
Team Website
Team : Dynamic Control of Signaling and Gene Expression
Team Website
29/10/2024
/
Thesis :
Funding :
29
Mechanical response and Waves in Active Solids
Domaines
Soft matter
Non-equilibrium Statistical Physics
Type of internship
Expérimental et théorique Description
Active matter describes systems in which the elementary constituents consume energy to produce work. In the past three years we have tailored an artificial system that combines activity and elastic architecture and demonstrated that selective and collective actuation is a hallmark of active solids https://twitter.com/i/status/1561626005520932864. These results open a brand-new avenue of research, from further experimental and numerical investigations to theoretical analysis. Examples of open questions are:
- What is the fate of collective actuation in the thermodynamics limit?
- Is there a transition controlled by noise and of what type?
- How does the sound propagate in such active solids?
- What is the mechanical response of such materials?
Depending on you, the internship can take a more experimental, more numerical or more theoretical direction.
Contact
Olivier Dauchot
29/10/2024
/
Thesis :
Funding :
30
Excitonic whispering gallery mode laser in high pumping regime
Domaines
Quantum optics/Atomic physics/Laser
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental et théorique Description
In nanophotonics and quantum technologies, photon sources are a ressource which can be integrated into a chip. Cylindrical dielectric microdisks make excellent resonators in which optical gallery modes can propagate at the air/dielectric interface.
Using optical lithography, we have fabricated gallery-mode resonators on which we have deposited fluorescent nano-emitters, colloidal quantum dots. These are CdS/CdSe/CdS semiconductors in a spherical core/shell/shell configuration. Of nanometric dimensions, their fluorescence wavelength depends on their size. They can emit single photons, are resistant to photobleaching and are bright under strong excitation. We have deposited these quantum dots in high concentration on microdisks, and excited them with a green laser. The excitons thus created enabled us to achieve a significant gain. We were therefore able to create gallery modes excitonic microlasers. [1].
The aim of this internship will be to study these gallery-mode lasers, and to understand their characteristics as a function of their size, of the excitation when it is close to the laser threshold or more higher...
[1] C. Kersuzan et al, ACS Photonics, 11(4), 1715-1723 (2024)
Contact
Agnes MAITRE
29/10/2024
/
Thesis :
Funding :
31
Generating nonclassical states of light using waveguide quantum electrodynamics
Domaines
Quantum optics/Atomic physics/Laser
Non-relativistic quantum field theory, quantum optics, complex quantum systems
Quantum information theory and quantum technologies
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
This internship offer is for a Master’s student interested in quantum optics, specifically in generating nonclassical states of light using waveguide quantum electrodynamics. The project, based at LKB, Jussieu campus, involves theoretical modeling and simulation of photon interactions with quantum emitters to create quantum states and understand their formation. The intern will perform theoretical calculations, develop computational models, and collaborate with the research team. Applicants should have knowledge in quantum mechanics or optics, and experience with Python is advantageous.
Contact
Hanna Le Jeannic
29/10/2024
/
Thesis :
Funding :
32
Flows and shapes of membrane with a protein inclusion
Domaines
Biophysics
Soft matter
Physics of liquids
Physics of living systems
Type of internship
Théorique, numérique Description
Many cellular functions rely on the ability of cells to alter their shape. At the cell-membrane level, shape changes are driven by forces which, regulated by specific proteins, alter the membrane curvature through structural alterations. We will study theoretically the fluid mechanics of a cell membrane—modelled as a two-dimensional fluid layer—including a trans-membrane protein.
In the absence of flows, the membrane shape is determined by a balance between Laplace pressure and bending rigidity. The presence of flows in the membrane fluid alters this picture: viscous forces stemming from the flow alter the membrane shape. This intertwinement between flows and shape may reveal novel, physical features, which we plan to study.
The strong points of this internship are:
Scientific publications will be aimed at the best scientific journals
The student will acquire valuable skills, such as proficiency in Python, learning and mastering of the finite-element method, and others, which will be highly beneficial for his/her future scientific career.
- The cross-disciplinary character of this internship, bridging between theoretical physics, differential geometry, experimental physics and biology, will offer numerous directions for future developments of the project.
See https://sites.google.com/site/michelecastellana/internship-proposals for more details.
Contact
Michele Castellana
Laboratory : PCC, Institut Curie - UMR168
Team : Dynamic Control of Signaling and Gene Expression
Team Website
Team : Dynamic Control of Signaling and Gene Expression
Team Website
28/10/2024
/
Thesis :
Funding :
33
Causal decompositions of unitary processes
Domaines
Relativity/Astrophysics/Cosmology
Quantum information theory and quantum technologies
Type of internship
Théorique, numérique Description
The conjecture of causal decompositions proposes that there is an equivalence between two fundamental structures of quantum theory: causal structure and compositional structure. It would provide a dramatic connection between an empirical, operationally accessible notion (causal structure) and a powerful mathematical structure (compositional structure). This conjecture has recently been proven in the case of 1D Quantum Cellular Automata (QCAs), (which can be seen as representing lightcone-abiding dynamics in a discretised (1+1)D Minkowski spacetime), using novel and powerful mathematical techniques that employ C* algebras. The proof is however limited to a finite number of spatial sites, because the techniques have only been developed for finite-dimensional C* algebras.
The project is for the students to generalise this proof to the infinite case, by investigating the extension of these techniques to the case of C* algebras of infinite dimension. This project is expected to require a significant deal of mathematics and abstraction, but the tools to be developed hold deep physical significance and promise to find application in other fields. The internship could continue into a PhD.
Contact
Augustin Vanrietvelde
28/10/2024
/
Thesis :
Funding :
34
Stability of Thin liquid films: silicone coatings for glass
Domaines
Soft matter
Physics of liquids
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 thickness in a timely manner. As examples, defects on glass substrates lead to thickness heterogeneities that grow over time rather than heal. When starting from a collection of droplets sprayed onto a flat substrate, a nanometer-thick film first spreads around the droplets, and delays the spreading and coalescence of the droplets.
The goal is to gain 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 chemically-modified silicon wafers, well-characterized silicone oils), and imaging techniques such as ellipsometry or profilometry will be used, in order to measure and model the time variation of silicone oil coatings.
Two cases will be particularly studied.
- Time evolution of oil spread onto substrates decorated will well-controlled defects
- Spreading dynamics of several droplets deposited on smooth substrates.
Contact
Emilie VERNEUIL
28/10/2024
/
Thesis :
Funding :
35
Drainage of thin liquid films and lifetimes of foams (experimental and theoretical)
Domaines
Soft matter
Physics of liquids
Type of internship
Expérimental et théorique Description
Coalescence has been widely studied in surfactant solutions. Nevertheless, a quantitative prediction of the lifetimes of liquid films stabilised by surfactants is still lacking due to intricate couplings between the flow and concentration fields as well as the disjoining pressure. Complexity arises from the timescales of surface and bulk transfers of surfactants. >Hence, the situation for surfactant solutions is so intricate that predicting the lifetime of a soap film remains a challenge. We have identified a very simple system in which it is possible to describe quantitatively the stability of liquid films. These are liquid mixtures, miscible in all proportions, for which: (i) disjoining pressure is always attractive and independent of local composition, (ii) surface/volume transfers are only controlled by diffusion, (iii) film lifetimes vary from 1ms to 10 s by changing the composition. Consequently, the question of coalescence and its consequences on diphasic flows is well posed in these systems.
The purpose of the internship is to describe the physical mechanisms acting to stabilize foams of two mixed liquids. We will perform experiments on suspended liquid films thanks to a specially designed cell. We will explore the effects of the curvature which sets the capillary pressure gradients and the drainage time. These experiments will be analyzed and compared to on-going numerical simulations to improve our understanding of the stabilizing mechanisms in oil foams.
Contact
Emilie VERNEUIL
28/10/2024
/
Thesis :
Funding :
36
Tunable dynamic behavior of kirigami in fluid flow
Domaines
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
In engineering, flexible components are increasingly favored over rigid ones for devices operating in fluid flow. Their ability to deform enhances resilience to changing conditions, and can improve aerodynamic performance, or support a range of operational modes. However, controlling their complex deformations under fluid loading presents significant design challenges, requiring innovative approaches. Recent work in LadHyX has shown the potential of kirigami—where cut patterns are introduced into flat materials—to create tunable poroelastic structures, providing effective control for passive shape adaptation in fluid environments. While past studies have mainly explored static shape changes, this internship seeks to broaden the focus to include the dynamic response of kirigami structures in fluid flow.
Contact
Sophie Ramananarivo
25/10/2024
/
Thesis :
Funding :
37
Collective phototaxis of colonial swimming microorganisms
Domaines
Biophysics
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Théorique, numérique Description
Using the microorganism Volvox we recently observed quite interesting behaviors: at an individual level Volvox exhibits directional phototaxis towards the light source, where the phototaxis mechanism can be explained by the orchestral coordination of the many cilia on its surface. At the collective level where the density of Volvox in the fluid is high, we observed that a population of Volvox exhibits distinct collective dynamics compared to individual behavior in response to light stimuli, where hundreds of Volvox cells form a stable, rotating two-dimensional layer of active crystal (aggregate) suspended in a three- dimensional fluid chamber.
In this project, we aim to establish a novel mechanistic framework that integrates experiments, theoretical analysis, and simulations to capture quantitatively the hydrodynamic interactions governing both individual and collective behaviors of microorganisms.
Contact
Blaise Delmotte
25/10/2024
/
Thesis :
Funding :
38
Periodic and chaotic fiber deformation in porous media
Domaines
Biophysics
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Théorique, numérique Description
The separation of elongated and/or deformable particles, such as microplastic fibers or pathogens, using structured media, such as pillar arrays, is essential for many processes such as pollution control, environmental assessments, diagnosis or biological analysis. However, it remains a highly challenging task due to the extensive range of morphologies fibers can adopt when interacting with flows and obstacles. Predicting and controlling the trajectory of elongated elastic structures in a flow embedded with obstacles is essential to understand the physics of biological and industrial systems but also to design efficient separation techniques.
The aim of this project is to investigate the migration of flexible fibers due to pressure-driven flows in structured media embedded with obstacles using theoretical models and numerical simulations. The intern will use theoretical analysis and numerical tools developed by the group of Blaise Delmotte at LadHyX, and will collaborate closely with the groups of Olivia du Roure and Anke Lindner at PMMH, where experiments are performed.
Contact
Blaise Delmotte
25/10/2024
/
Thesis :
Funding :
39
A mean-field game approach for balancing intermittent power generation and consumption in electrical networks
Domaines
Statistical physics
Type of internship
Théorique, numérique Description
The system for producing (and consuming) electrical energy is undergoing a profound transformation, driven by two factors whose impact will increase significantly in the coming decades. On the one hand, the growing share of intermittent sources (solar, wind) in the energy mix and, on the other hand, technological advances that will make it increasingly possible to control the use of electrical appliances in households. Adapting this intermittent production to consumption will be one of the main challenges of the energy transition in the coming decades.
The aim of the two internships proposed will be to address this problem in a simplified setting where ``agents'' are both electricity producers and consumers and to study the coordination between the agents within a game theoretic approach. This will imply two tasks, each the subject of an internship: i) the construction and study of a Mean Field Game describing the behavior of the agents, and ii) to take the point of view of the ``central authority'', leading to a problem of ``game design'' .
Contact
Denis Ullmo
Laboratory : LPTMS - UMR 8626
Team : Disordered systems, soft matter, interface physics
Team Website
Team : Disordered systems, soft matter, interface physics
Team Website
23/10/2024
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Thesis :
Funding :
40
La microfluidique sur un fil…
Domaines
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Contact
Alexis Duchesne
23/10/2024
/
Thesis :
Funding :
41
Microstreaming for acoustically excited micro-swimmers
Domaines
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Contact
Alexis Duchesne
23/10/2024
/
Thesis :
Funding :
42
Oscillations of a micro hydraulic jump
Domaines
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Contact
Alexis Duchesne
23/10/2024
/
Thesis :
Funding :
43
Dynamique extraordinaires d’interface liquides couvertes de microparticules
Domaines
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
L’ajout de microparticules sur une interface liquide-air peut drastiquement modifier les propriété mécaniques et physique de cette interface et conduire à des comportement surprenants, comme des bulles non-sphérique stables (par exemple cylindriques), des « bulles d’air éternelles» résistant au drainage et à l’évaporation et pouvant ainsi conserver leur intégrité pendant plus d’un an ou encore l’inversion de l’instabilité de Saffman-Taylor.
A l’heure actuelle, le comportement dynamique de ces interfaces reste encore largement inexploré. Au cours de ce projet de master, nous étudierons expérimentalement et théoriquement des aspects originaux de la réponse dynamique de ces interfaces et en particulier leur propriétés mécaniques/physiques pour différents objets et différentes compositions d’interface.
Contact
Alexis Duchesne
23/10/2024
/
Thesis :
Funding :
44
Impact d’un jet sur une surface chaude
Domaines
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
L’étude de l’impact d’un jet liquide vertical revêt une importance capitale dans de nombreuses applications comme le nettoyage et le refroidissement. Il s’agit, en effet, d’un processus bien connu dans de nombreux secteurs industriels.
L’impact d’un jet sur une plaque chaude a donc fait l’objet d’une abondante littérature mais la question n’a jusqu’ici été abordé que d’un point de vue thermique.
Dans des travaux récents, notre équipe a étudié les aspects hydrodynamiques du problème. Nous avons constaté la transition entre deux régimes distincts : l'un où une goutte s'élargit à son point d'impact, et l'autre où elle se fragmente en un spray. Dans ce second régime, le liquide s'étale sur la surface en formant une couche qui finit par se détacher et se fragmenter en gouttelettes sous l'effet de l'évaporation.
L'objectif de ce stage est de poursuivre l'exploration de l'impact d'un jet liquide sur une plaque chaude, en approfondissant plusieurs aspects supplémentaires. Nous examinerons notamment la configuration d'un jet incliné, ainsi que les conditions menant à l'apparition d'un rebond du jet, tel qu'observé expérimentalement. L'effet d'un jet préchauffé sur le comportement global du système sera également étudié. Enfin, l'influence d'une surface rugueuse, texturée ou hydrophobe sur le processus de fragmentation du jet sera explorée.
Contact
Alexis Duchesne
23/10/2024
/
Thesis :
Funding :
45
Interaction médiée par la déformation d’un film de savon
Domaines
Condensed matter
Soft matter
Physics of liquids
Relativity/Astrophysics/Cosmology
Fields theory/String theory
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
Lorsque l’on dépose un petit objet sur un film de savon horizontal, la masse de l’objet déforme le film. Cette déformation du film crée un potentiel qui attire tout autre objet présent sur le film. La présence de cette interaction a permis d’observer dans notre laboratoire que deux gouttes posées avec une vitesse initiale sur un film de savon orbitent l’une autour de l’autre, selon des trajectoires analogues à celles observées pour de grandes structures cosmologiques.
Pour aller plus loin, il est nécessaire de modéliser la force d’interaction entre objets, médiée par la déformation du film de savon sous l’effet de leur propre masse.
Le but de ce projet de master, est de mesurer expérimentalement, et modéliser théoriquement la force d’interaction entre deux objets posés sur un film de savon. Nous caractériserons d’abord le lien entre déformation locale du film et force d’interaction puis utiliserons cette modélisation pour décrire finement les trajectoires d’objets en interactions, déjà observées au laboratoire.
Contact
Alexis Duchesne
23/10/2024
/
Thesis :
Funding :
46
Clustering of particles floating on a vibrated liquid surface
Domaines
Statistical physics
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
When several particles float on the surface of a liquid, they tend to cluster together. This phenomenon results from capillary attraction, sometimes called "Cheerios effect". In this project, we aim to study what happens to a cluster of floating particles in the presence of capillary waves in the Faraday geometry (thin liquid layer subjected to vertical vibration). The vertical oscillation can trigger standing waves on the surface, known as Faraday waves, which will interact with the particles.
The first goal of the project is to experimentally explore the behavior of a large number of spheres under capillary interaction and for varying vibration amplitudes. Depending on the surface density of the spheres and the vibration amplitude, we expect collective behavior similar to that of gas (dilute medium with disordered movements), liquid (denser medium with highly correlated movements), or solid (very dense medium with crystalline order and defects).
The existence of these different phases is very common for interacting particles. The question is whether Faraday waves play a role similar to temperature. In a second phase, the floating spheres will be replaced with particles of more complex shapes, such as elongated particles that may exhibit local alignment properties, in order to study the influence of this local order on aggregation properties.
Contact
Frederic Moisy
22/10/2024
/
Thesis :
Funding :
47
How salt-infused nanosponges respond to humidity changes
Domaines
Condensed matter
Statistical physics
Soft matter
Physics of liquids
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
We are interested in fundamental physics problems that are relevant in various important societal and engineering contexts. In particular, we study how evaporation and condensation of salty water happens in complex systems, triggered by variations in external humidity. These phenomena are crucial for e.g. water harvesting in dry climates, cloud formation in the atmosphere, new strategies for energy production/conversion, smart optical/mechanical metamaterials, sustainable architecture and heritage conservation, etc. but raise basic, unexplored question with rich physics. Recently, we have successfully characterized and described how the interaction between condensation/evaporation and capillary/osmotic phenomena dictate the equilibrium states of salt solutions confined in single nanopores. Now we are investigating larger scale phenomena in extended systems formed of many interacting pores (formation of arrays of microdroplets, stochastic nucleation patterns) and are trying to understand how they emerge from the behavior in single nanopores.
Contact
Olivier Vincent
22/10/2024
/
Thesis :
Funding :
48
Bubble fronts in tree-like structures
Domaines
Condensed matter
Statistical physics
Biophysics
Soft matter
Physics of liquids
Physics of living systems
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
When plant tissues are subjected to dry conditions, bubbles can spontaneously form in the complex vascular network of trees (xylem) conducting water, resulting in the embolism of these tissues (Fig. a-b). With climate change, it is thought that such events will occur more frequently and threaten the survival of forests and crops. However, the physics of the appearance, growth, and propagation of the bubbles in xylem (which combines microscale vessels, variations in wettability, and random, nanoscale membranes) is still poorly understood. With a combination of numerical simulations and experiments, we aim at establishing the general features of bubble propagation in xylem-like structures, and how the nonlinear coupling between several mechanisms (stochastic bubble nucleation, diffusion-limited growth, capillary breakthrough, poroelastic relaxations, osmotic phenomena, etc.) dictate the dynamics and patterns of gas invasion in disordered structures.
Contact
Olivier Vincent
22/10/2024
/
Thesis :
Funding :
49
Humidity-controlled micro/nano-fluidics
Domaines
Condensed matter
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
The interaction between water in materials and external humidity dictates a wide range or natural and technological processes (e.g. plant physiology, water harvesting/purification strategies, energy transport/storage, construction materials, soil science, etc.). We are interested in synthetic micro/nano-fluidic systems where the water content and transport dynamics are controlled by external changes in humidity. One way to obtain spontaneous filling/emptying of water is to combine confinement and solute-induced effects. The internship aims at characterizing the filling/emptying response of micro and nanochannels containing salt solutions to humidity changes, and to characterize how the competition between various effects (capillarity, osmosis, phase change: evaporation, condensation, crystallization, deliquescence, etc.) dictate the phase diagram of filling state as a function of humidity, and the dynamics of these processes. Interestingly, the results of these fundamental investigations can be directly transferred in an ongoing European project aiming at harvesting electrical energy from natural from natural or industrial humidity cycles.
Contact
Olivier Vincent
22/10/2024
/
Thesis :
Funding :
50
ENERGY AND MATERIAL INVESTMENT IN RAILWAY DEVELOPMENT DURING THE INDUSTRIAL REVOLUTION
Domaines
Statistical physics
Non-equilibrium Statistical Physics
Type of internship
Théorique, numérique Description
The development of energy transmission and distribution networks is often a blind spot in forecasts of the energy transition, even though they are recognized as central to the use of low-carbon energies. We propose to explore the historical case of the development of the railway network in the 19th century, in terms of the consumption of material and energy resources for its construction, maintenance and use. Our ambition is to understand the link between the dynamics of transport development and economic growth based on coal, both the raw material of the network and the beneficiary of its development. We will make use of the results already obtained by graph theory applied to these spatial networks, and will draw on a similar approach underway for electricity networks. The aim of the internship will be to gather documentary resources, define the geographical study area in line with available data, and present an initial network development model.
Contact
Hervé BERCEGOL
21/10/2024
/
Thesis :
Funding :
51
Modélisation et étude des fluctuations d’une membrane biologique
Domaines
Statistical physics
Biophysics
Soft matter
Physics of living systems
Type of internship
Théorique, numérique Description
La caractérisation de l’amplitude des fluctuations d’une membrane biologique fournit une mesure indirecte de ses propriétés mécaniques. Dans ce projet de stage, nous proposons de caractériser les fluctuations thermiques d’une membrane en utilisant différentes approximations de l’Hamiltonien H décrivant l’énergie de la membrane. Par souci de simplification, nous modéliserons une membrane à une dimension contenue dans le plan.
Deux tensions différentes peuvent être définies pour une membrane : sa tension intrinsèque, γ, variable intensive conjuguée de la longueur L de la membrane, et sa tension de cadre, τ , conjuguée de sa longueur projetée Lp . On cherchera à déterminer numériquement la relation entre ces deux tensions et l’amplitude des fluctuations de la membrane, et comment l’utilisation des différentes approximations de H altère cette relation.
Contact
Marc Durand
Laboratory : MSC - UMR7057
Team : Morphogenèse et Dynamique des Systèmes Auto-Organisés
Team Website
Team : Morphogenèse et Dynamique des Systèmes Auto-Organisés
Team Website
20/10/2024
/
Thesis :
Funding :
52
3D nematic-like tissues : Mechanical and electrical constraints to orchestrate muscle cell differentiation.
Domaines
Statistical physics
Biophysics
Physics of living systems
Type of internship
Expérimental Description
Development is driven by robust processes across scales and functions. Physics of liquid crystals reveals as fruithfull in describing the evolution of spindle-shaped cells such as myoblasts. We focus on muscle precursors to create multicellular capillary bridges and to apply forces on these nematic-like micro-tissues in 3D. This mechancal constraints allows to obtain multilayererd actin structure mostly aligned. The internship aims to explore how competiting electrical cues mimicking motoneurons stimulation can interfere in this architecture. The project involves monitoring actin filament dynamics using 2-photon microscopy, and identify applying optogenetic stimulation.
Contact
Myriam REFFAY
19/10/2024
/
Thesis :
Funding :
53
3D nematic-like tissues : Topological dynamics and interplay with muscle cell differentiation.
Domaines
Statistical physics
Biophysics
Physics of living systems
Type of internship
Expérimental Description
Development is driven by robust processes across scales and function. Physical description in term of physics of liquid crystals reveals as fruithfull in describing the evolution of spindle-shaped cells as myoblasts. We focus on muscle precursors to create multicellular capillary bridges and to apply forces on these nematic-like micro-tissues in 3D.
The internship aims to study the creation and annihilation of topological defects in 3D tissue under mechanical constraints. These defects are known to influence differentiation, as seen in myoblast patterns and model organisms like hydra. The project involves monitoring actin filament dynamics using 2-photon microscopy, and identify differentiation patterns.
Contact
Myriam REFFAY
19/10/2024
/
Thesis :
Funding :
54
Quantum imaging using high harmonic states of light
Domaines
Quantum optics/Atomic physics/Laser
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 main objective of the internship will consist in using a pair of non-degenerated entangled photons at 2 harmonics from the high harmonic frequency comb to perform a quantum imaging experiment . We will study the possibility of transferring the sensing and resolution benefit from one spectral range to another one.
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. Ultimately, the candidate will investigate novel protocols to create high-resolution label-free images of complex structures (e.g. cells) embedded inside biological tissues.
Contact
Hamed Merdji
18/10/2024
/
Thesis :
Funding :
55
Multipartite entanglement in semiconductor high harmonic generation
Domaines
Quantum optics/Atomic physics/Laser
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
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 the process of high harmonic generation in semiconductors 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 will verify genuine multipartite entanglement of the photons in the time/frequency domain. The approach will be further extended to verify multi-partite entanglement between even more optical modes.
Contact
Hamed Merdji
18/10/2024
/
Thesis :
Funding :
56
Multipartite entanglement in semiconductor high harmonic generation
Domaines
Quantum optics/Atomic physics/Laser
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
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 the process of high harmonic generation in semiconductors 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 will verify genuine multipartite entanglement of the photons in the time/frequency domain. The approach will be further extended to verify multi-partite entanglement between even more optical modes.
Contact
Hamed Merdji
18/10/2024
/
Thesis :
Funding :
57
Attosecond control of quantum states of light
Domaines
Quantum optics/Atomic physics/Laser
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
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 quantum states of light well before the decoherence of the system occurs. We recently reported the violation of the Cauchy-Schwarz inequalityas as a direct test of multipartite entanglement in the HHG process. The internship will consist in realizing a platform that will allow controlling the HHG quantum state on attosecond time scale, This opens the vision of quantum processing on unprecedented timescales, an evident perspective for future quantum optical computers. For M2 students: only candidates motivated to follow with a PhD in this topic will be considered. L3 and M1 students are welcome.
Contact
Hamed Merdji
18/10/2024
/
Thesis :
Funding :
58
Non-Euclidean photonics & Quantum chaos
Domaines
Quantum optics/Atomic physics/Laser
Relativity/Astrophysics/Cosmology
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
Type of internship
Expérimental et théorique Description
Quantum chaos is a research field dedicated to semi-classical physics [1], ie. the relationship between a quantum system and its classical counterpart. The predictions are investigated in any wave system, namely quantum, acoustic, microwaves, optics,… One of the major hypothesis is the localization of eigenmodes on classical periodic trajectories.
Recently, we demonstrated the fabrication of surface-like microlasers by Direct Laser Writing (DLW). The laser modes were indeed located along periodic geodesics [2] (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. In spherical squares, for instance, the geodesics are stable (Fig. bc). During the internship, the student will investigate microlasers based on a pseudosphere, a surface with constant negative curvature (Fig. e), where geodesics are unstable and the classical dynamics is chaotic [3].
The microlasers are fabricated by Dominique Decanini, the FDTD simulations are performed by Xavier Chécoury, the experiments are carried out by Mélanie Lebental, and the theory is developed by Barbara Dietz. The student will be involved in some of these tasks according to his/her likings.
Contact
Mélanie Lebental
18/10/2024
/
Thesis :
Funding :
59
Images des points singuliers dans la surface de Bloch généralisée
Domaines
Condensed matter
Non-relativistic quantum field theory, quantum optics, complex quantum systems
Topological materials, Quantum Transport, Cavity Quantum Electrodynamics
Type of internship
Théorique, numérique Description
La surface de Bloch généralisée est une surface classifiante plongée dans un espace de dimension 7. Elle permet de déterminer si un chemin de l'espace réciproque est trivial ou non. Les chemins non triviaux tournent autour de points singuliers. On veut plus précisément étudier l'image des singularités du modèle de Haldene généralisé. Plus précisément, leur voisinage, qui est constitué de cones de la surface de Bloch se rejoignant en ces points.
Contact
Gilles Abramovici
17/10/2024
/
Thesis :
Funding :
60
Test of quantum electrodynamics in strong Coulomb field
Domaines
Quantum optics/Atomic physics/Laser
High energy physics
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
17/10/2024
/
Thesis :
Funding :
61
Light in Complex Media : from imaging to computing
Domaines
Quantum optics/Atomic physics/Laser
Quantum Machines
Quantum information theory and quantum technologies
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 Description
Scattering of light in heterogeneous media, for instance the skin or a glass of milk, is usually
considered an inevitable perturbation or even a nuisance. Through repeated scattering and
interferences, this phenomenon seemingly destroys both the spatial and the phase information
of any laser illumination.By « shaping » or « adapting » the incident light, it is in principle possible to control the propagation and overcome the scattering process. This concept has been exploited in the last decade to focus and image through and in complex media, and opens important prospects for imaging at depth in biological media.
In the group we are currently exploring two main topics, combining synergistically optical design and numerical studies for : (a) non-invasive coherent (SHG, Raman) and incoherent (multiphoton fluorescence) imaging, leveraging computational microscopyconcepts and (b) exploiting random mixing induced by the propagation of light through a complex medium for various computational tasks, allowing the intriguing concept of computing with disorder.
We have multiple funded ongoing projects along these two directions and welcome motivated
applicants for internship, with a solid background in physics, and an interest in machine learning, optics, imaging and computing.
Contact
Sylvain Gigan
16/10/2024
/
Thesis :
Funding :
62
Solutions aérauliques pour la protection des équipements sensibles en environnement industriel
Domaines
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Théorique, numérique Corporate activity
Description
La conduite des procédés industriels se base sur de nombreux instruments régulant le fonctionnement de la production. Ces appareils particulièrement sensibles sont exposés à des atmosphères qui leur sont hostiles en raison des températures élevées, ou encore du fait de la présence de poussières et de vapeurs. Une solution pour protéger ces équipements consiste à les isoler de l'atmosphère ambiante par des jets d'air judicieusement dirigés. Toutefois, la conception de tels dispositifs de protection aéraulique reste limitée à une approche purement empirique. Si des solutions ont été trouvées pour des contextes spécifiques, elles s'avèrent difficilement transposables sans une meilleure compréhension des principes de fonctionnement de la protection aéraulique.
Nous recrutons un·e étudiant·e stagiaire pour aborder le problème multi-physique de la protection aéraulique des équipements industriels sensibles. L'objectif sera d'en déterminer les principes généraux et de proposer des solutions assurant systématiquement une bonne isolation vis-à-vis d'atmosphère hostiles. La personne en charge de l'étude aura notamment à sa disposition des moyens de simulation numérique, ainsi que des données collectées en usine sur des dispositifs existants. Elle pourra également bénéficier de l'expertise du groupe auquel est rattaché le stage en physique des fluides, thermique, mécanique et optimisation.
Contact
Thomas Le Reun
16/10/2024
/
Thesis :
Funding :
63
Dissociation active de condensats biomoléculaires
Domaines
Biophysics
Physics of liquids
Nonequilibrium statistical physics
Type of internship
Expérimental et théorique Description
Un grand nombre de travaux ont été consacrés au cours de la dernière décennie aux organites sans membrane, également appelés condensats biomoléculaires, qui se révèlent assurer plusieurs fonctions essentielles dans les cellules. Ce stage portera sur des fluides ternaires composés d'un solvant aqueux tamponné, de peptides cationiques, et d'ARN, afin de mimer des condensats biomoléculaires réels présents dans les cellules vivantes. Ces fluides présentent une concentration critique en peptides, au-delà de laquelle des condensats stables émergent selon un processus de séparation de phase liquide-liquide. Dans ce projet, la cinétique de dissociation de ces condensats sera explorée dans des conditions hors équilibre, comme cela se produit dans l'environnement intracellulaire.
Contact
Guillaume TRESSET
16/10/2024
/
Thesis :
Funding :
64
Deep learning of scale free processes
Domaines
Statistical physics
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Type of internship
Théorique, numérique Description
In the statistical physics context many problems of interest, related to critical phenomena are associated to fractal structures. This problem is notoriously difficult with standard ML.
Taking the percolation problem as a study case the task will consist to regress from images of percolation states the size of the maximal cluster and whether it is a spanning cluster via new ML algorithms. A second and related task would be to consider different 2D conformal field theory, characterized by some fractal exponents ot their central charge.
Contact
Sergio Chibbaro
15/10/2024
/
Thesis :
Funding :
65
Fabrication and characterization of gradient soft solids
Domaines
Soft matter
Type of internship
Expérimental et théorique Description
The aim of this project is to establish the link between fabrication protocols and mechanical gradients, in model soft solids. The fabrication method will rely on layering, a technique at the basis of 3D printing, and the characterization on micromechanics experiments, which allow for the visualization of materials displacements in the three spatial directions. Beyond opening new ways to design and control soft solids, this project will have far-reaching fundamental implications in the fields of multiphasic materials, 3D printing, and polymer physics.
Contact
Nicolas Bain
15/10/2024
/
Thesis :
Funding :
66
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
15/10/2024
/
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
15/10/2024
/
Thesis :
Funding :
68
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
15/10/2024
/
Thesis :
Funding :
69
Macroscopic friction of fibrous assemblies
Domaines
Soft matter
Physics of liquids
Physics of living systems
Type of internship
Théorique, numérique Description
The objective of the internship is to study numerically the stability of heaps of entangled fibres under gravity, and investigate the impact of microscopic quantities (length and natural curvature of the fibres, friction between fibres) on the limit angle attainable with static macroscopic heaps. These numerical experiments will in particular help identify the relevant non-dimensional microscopic parameters which control the macroscopic static friction of the medium.
Contact
Thibaut METIVET
14/10/2024
/
Thesis :
Funding :
70
Numerical modelling of granular avalanches through a forest of deformable pillars
Domaines
Soft matter
Physics of liquids
Physics of living systems
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
14/10/2024
/
Thesis :
Funding :
71
Locomotion in granular media
Domaines
Soft matter
Physics of liquids
Physics of living systems
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
Many living species thrive in granular environments, such as sand. Navigating through these granular terrains poses significant challenges, as these materials are heterogeneous, highly dissipative, and exhibit complex mechanical responses. As a result, animals serve as a remarkable source of bioinspiration for developing efficient strategies to move in such environments. At the FAST laboratory, we experimentally investigate the various strategies employed by animals to traverse sandy substrates, assessing their effectiveness and robustness. To this end, we develop bio-inspired robots and active systems, studying their behavior within a model granular environment. The goal of these experiments is to understand the underlying physics governing the interactions between moving objects and granular materials. If you are interested in animal locomotion, the mechanics of granular materials, or robot design and control, please contact us.
Contact
Baptiste Darbois Texier
14/10/2024
/
Thesis :
Funding :
72
Multiscale temporal nonlinear optical response of a biased crystal
Domaines
Condensed matter
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. 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. A major challenge in the field of quantum fluids of light is to increase its dimensions. An interesting strategy [2] is to consider ultrashort pulses rather than continuous propagation and combine both the instantaneous electronic Kerr effect with the slow photorefractive nonlinear effect [3].
[1] C. Michel et al, Nat. Commun. 9, 2108 (2018)
[2] P.-\'E. Larr\'e et al, PRA 92, 043802 (2015)
[3] O. Lahav et al, PRX 7, 041051 (2017)
Contact
Claire Michel
11/10/2024
/
Thesis :
Funding :
73
Friction and elasticity of folded polymer films
Domaines
Soft matter
Type of internship
Expérimental et théorique Description
Thin elastic sheets or wires easily fold when deposited on substrates. The relaxation of these folds or wrinkles depend on the ability of the sheet to slide on the substrate, while the elastic energy stored in the folds or wrinkles promotes the relaxation of the shape. Hence, such problems interestingly couple elasticity to frictional and sliding behaviors in thin elastic sheets.
The internship aims at exploring several aspects : How does the interplay between film deformation and friction affect the development of buckling instabilities and fold trapping? What is the contribution of film roughness and polymer viscoelasticity? To answer to these questions, we will carry out experiments in which a viscoelastic polymer strip is laid at imposed vertical velocity on a glass plate while the development of buckling instabilities and friction at the rough contact area at the glass/strip interface are continuously monitored. Based on these observations, we will seek to develop a physical description of the role of friction in the formation and trapping of wrinkles in relation to the mechanical and roughness properties of the polymer film.
Contact
Emilie VERNEUIL
10/10/2024
/
Thesis :
Funding :
74
Non-linear response theory in self-gravitating systems
Domaines
Statistical physics
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Kinetic theory ; Diffusion ; Long-range interacting systems
Type of internship
Théorique, numérique Description
Gravity is a long-range interaction. As a result, stellar systems are generically (i) inhomogeneous (stars follow intricate orbits), (ii) self-gravitating (stars self-consistenly define the gravitational potential), (iii) resonant (orbits introduce orbital frequencies). In the limit of small perturbations, the efficiency with which a stellar system responds to stimuli is described by linear response theory, a successful framework to predict (linear) modes. Yet, as a stellar systems nears an instability, amplification gets so large that fluctuations are no longer small. This is the realm of non-linear response theory, whose analytical description is much more challenging.
This internship focuses on exploring non-linear response theory in stellar systems. For that purpose, we will investigate the "periodic cube", an enlightening self-gravitating toy model. We will explore the dependence of the level of thermal fluctuations, as one lowers the system's dynamical temperature. We will use stochastic methods from renormalisation theory, originating from plasma physics, to predict the associated levels of perturbations. Ultimately, this program of research will offer new clues on non-linear self-gravitating processes, such as mode saturation and statistical correlation functions.
Contact
Jean-Baptiste Fouvry
10/10/2024
/
Thesis :
Funding :
75
Patterns generated by erosion by dissolution
Domaines
Soft matter
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
Erosion by dissolution plays a significant role in area covered by a soluble mineral like in Karst regions and is the cause of the formation of remarkable patterns (limestone pavements, scallops, dissolution channels, dissolution pinnacles, limestone forests…) with characteristic length scales. We propose in this internship, by the mean of controlled laboratory experiments, to study the morphogenesis of dissolution patterns. The soluble media and the hydrodynamic flows will be tuned to downscale the characteristic size and time of the involved processes from geological values to “laboratory” values. Thanks to quantitative measurements of the flow and of the topography of eroded surfaces, we will identify the driving elementary physical mechanisms and thus develop mathematical models and numerical simulations, with the aim to explain complex geological systems and to predict the long term evolution of landscapes.
In this internship, the student will develop in the group, one or several model experiments, reproducing dissolution erosion phenomena. To decrease the timescales, fast dissolving materials like salt and plaster will be used. Hydrodynamic properties of the flows will be characterized and the 3D shape evolution of eroded surfaces will be recorded.
Contact
Michael Berhanu
10/10/2024
/
Thesis :
Funding :
76
Est-ce que les effets de marées impactent la masse des étoiles ?
Domaines
Relativity/Astrophysics/Cosmology
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Théorique, numérique Description
La compréhension du scénario global de la formation des étoiles reste l'une des questions ouvertes les plus difficiles en astrophysique.
Dans ce stage, nous chercherons à faire un pas en avant vers la compréhension de la Fonction de Masse Initiale (IMF) des étoiles, et de son apparente universalité.
Deux études numériques récentes (Lee & Hennebelle 2018b, Colman & Teyssier 2020) ont mis en évidence le rôle des interactions de marée entre les futures étoiles (appelées noyaux pré-stellaires) dans la détermination de la valeur du pic apparemment universel de l'IMF. Cependant, leurs résultats, et notamment l'interprétation actuelle du champ de marée empêchant la formation des structures dans un certain domaine autour de la future étoile, ont été récemment remises en cause par une étude analytique (Dumond & Chabrier, subm. à A&A).
Cependant, comme toutes les études analytiques, leurs résultats dépendent d'hypothèses fortes sur les propriétés de la structure (dont l'homogénéité statistique) et sont basés sur une approche globale pour déterminer sa stabilité (théorème du viriel tensoriel). Il est donc primordial de confronter cette théorie à des expériences numériques afin de tester et d'étendre les résultats analytiques à des cas plus réalistes. Compte tenu de l'impact des résultats attendus, nous estimons que le stage débouchera probablement sur une publication dans une revue à comité de lecture.
Contact
Jérémy Fensch
09/10/2024
/
Thesis :
Funding :
77
Dissipation and Decoherence in a Quantum System
Domaines
Condensed matter
Quantum Machines
Non-relativistic quantum field theory, quantum optics, complex quantum systems
Quantum information theory and quantum technologies
Type of internship
Expérimental Description
http://tiny.cc/QG
What happens to the ground state of a quantum system when we add dissipation? How is the lifetime of excited states affected by dissipation? How is quantum coherence destroyed by dissipation? The student will measure the lifetime and coherence of a bad qubit: a Josephson junction shunted by an on-chip resistance and embedded in a superconducting microwave cavity. The student is expected to aid in the design of devices using microwave simulation software; fabricate samples in a clean room using techniques such as microlithography and electron beam evaporation; cool samples using a cryogen free dilution cryostat; and make sensitive microwave measurements at low temperatures
Contact
Çağlar Girit
08/10/2024
/
Thesis :
Funding :
78
The Capillarytron for benchmarking AI-based inference of the mechanics of tissue morphogenesis
Domaines
Biophysics
Soft matter
Physics of liquids
Physics of living systems
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
What role do mechanical forces play in morphogenesis? Can we describe a growing multi-cellular tissue, in which the coupling between mechanics, chemistry and biology is permanent, as a lowing "complex luid"? What would be the `rheology’ of such a medium? These questions are currently central to developmental biology and health applications, but also pose major challenges for physics and engineering. The aim of this project is to tackle these questions using a biomimetic approach, based on the skills in rheology and modeling of complex luids and living environments present at IUSTI and IRPHE.
Contact
Simon Gsell
08/10/2024
/
Thesis :
Funding :
79
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
07/10/2024
/
Thesis :
Funding :
80
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
07/10/2024
/
Thesis :
Funding :
81
Energy-space sub-diffusion in driven disordered Bose gases
Domaines
Non-equilibrium Statistical Physics
Kinetic theory ; Diffusion ; Long-range interacting systems
Quantum gases
Type of internship
Théorique, numérique Description
During this M2 internship, we propose to study theoretically and numerically the dynamics of Bose gases subjected to both an oscillating driving force and a spatially disordered potential. This scenario, recently realized experimentally, gives rise to an original mechanism of sub-diffusion in energy space, whose quantitative description for realistic models of disorder remains to establish. This is the task that will be accomplished during this internship. More generally, this internship will be an opportunity to become familiar with the modern research fields of non-equilibrium quantum physics and ultracold Bose gases.
Contact
Nicolas Cherroret
05/10/2024
/
Thesis :
Funding :
82
Dynamic shape-morphing control via fluid structure interaction.
Domaines
Biophysics
Soft matter
Physics of liquids
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental et théorique Description
In Nature, living materials are constantly evolving and adapting their shape to the environment, a feat that is lacking in engineered materials. To achieve this, differential growth within the tissues is key, as it induces mechanical stresses and thus the buckling in a rich variety of shapes. Over the last decade, emerging approaches have embraced this paradigm to develop bioinspired synthetic responsive materials (to external stimuli, such as, temperature, magnetic field, pressure) with in-plane distortions, and hence shape-morphing capabilities. However, despite rapid developments, current efforts primarily focus on programming the final equilibrium shape, overlooking both the dynamical trajectory of the transformation and the mechanics of the morphed structure. As a result, exciting biomedical applications perspective in minimally invasive surgery, rehabilitation and soft robotics remain so far beyond reach.
In this internship, you will develop 3D-printed soft architected structures containing a network of interconnected cavities. By controlling the flow and the pressure distribution within the soft architected structure, the aim will be to characterize and then rationalize the fluid structure interaction at play to program the shape changes in space and time.
The internship can be followed by a PhD grant funded by the ERC Starting Grant DynaMorph.
Contact
Emmanuel SIEFERT
04/10/2024
/
Thesis :
Funding :
83
Gravitational collapse of a granular column reinforced with fibres
Domaines
Soft matter
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
Introducing a small amount of flexible fibres into a granular medium is known to significantly increase the mechanical strength of the material. However, little is known about the flowing behaviour of grain/fibre mixtures. The aim of this internship is to study the effect of the addition of fibres on the flow behaviour of a granular column collapsing under the effect of gravity. We will quantify the collapse dynamics of the column and the final shape of the deposit as a function of the volume fraction of the fibres, their aspect ratio and their flexibility
Contact
Baptiste Darbois Texier
04/10/2024
/
Thesis :
Funding :
84
Study of the photophysics of phototransformable fluorescent proteins for improved super-resolution microscopy
Domaines
Biophysics
Physics of living systems
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
We have recently demonstrated the significant benefits of event-based sensors in single-molecule localization microscopy (SMLM) super-resolution imaging. Surpassing the performance of traditional scientific cameras, these sensors expand the horizons of temporal resolution in SMLM. Event-based sensors, inspired by the human eye, are characterized by their asynchronous and independent pixels, which detect changes in brightness with high temporal precision. Thus, the EveSMLM technique (event-based SMLM) notably allows for capturing detailed profiles of intensity fluctuations and blinking of each observed molecule. This internship focuses on exploring the EveSMLM technique for studying the photophysics of photoconvertible fluorescent proteins.
Contact
Ignacio Izeddin
04/10/2024
/
Thesis :
Funding :
85
Bringing a cold-atom interferometer to the quantum noise detection limit
Domaines
Quantum optics/Atomic physics/Laser
Quantum information theory and quantum technologies
Quantum gases
Metrology
Type of internship
Expérimental Description
Cold atom inertial sensors have many applications in fundamental physics (testing the laws of gravitation, gravitational astronomy), geosciences (measuring the Earth's gravity field or rotation) and inertial navigation. The operation of these sensors is based on atomic interferometry, taking advantage of superpositions between quantum states of different momentum in an atom, generated by optical transitions with two (or more) photons. To broaden their range of applications, it is necessary to constantly push back their performance in terms of sensitivity, stability, precision, dynamic range, compactness or robustness, ease of use and cost. The aim of this Master project will be to study and improve our state-of-the-art SYRTE's cold atom gyroscope by one order of magnitude compared with the current state of the art to reach the interferometer's detection limit, which is intrinsically linked to quantum projection noise. It will use new methods like successive joint measurements without dead time. Obtaining this regime requires some modifications to the existing experiment, in particular to the Raman lasers used to manipulate the atomic wave packet, but also to the preparation and the detection of the atomic samples. This method is very general and could also be applied to more common three-pulse interferometers such as accelerometers and gravimeters.
Contact
Arnaud Landragin
04/10/2024
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Thesis :
Funding :
86
Connecting dark matter and galaxies with machine learning.
Domaines
Relativity/Astrophysics/Cosmology
Nuclear physics and Nuclear astrophysics
Type of internship
Théorique, numérique Description
Event Dark matter (DM) is the greatest unsolved mysteries in cosmology and physics, and mostly hidden from the current observations. The DM distribution can be inferred from observed galaxy distributions, but their relation is complex. To learn the spatial correlation between DM and galaxies, we combine hydrodynamic simulations and machine learning techniques. Hydrodynamic simulations can predict the spatial correlation between DM and galaxies, which can be learned by state-of-the-art machine learning technique. This project aims to reveal the DM distribution in the real Universe using the current observation of galaxies
Contact
Michel Gonin
03/10/2024
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Thesis :
Funding :
87
Machine Learning Event Reconstruction in Neutrino Physics
Domaines
High energy physics
Type of internship
Théorique, numérique Description
Event reconstruction algorithms are used to infer the particle properties, such as energy and direction, based on the photosensor information. Traditional likelihood-based algorithms use several approximations in the modeling of the detector that limit its accuracy and speed, which must be improved for Hyper-K. Several algorithms (DNNs; ResNet CNN, GNN, PointNet, UNet) have been adapted to our particular data format and need to be applied to real physics data. Two positions are available for this project:
a) application to CERN particle beam data in the Water Cherenkov Test Experiment,
b) application to Super-K cosmic ray and atmospheric neutrino data.
Contact
Michel Gonin
03/10/2024
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Thesis :
Funding :
88
Uncovering new radio-loud active galactic nuclei
Domaines
Relativity/Astrophysics/Cosmology
Nuclear physics and Nuclear astrophysics
Type of internship
Expérimental et théorique Description
A fraction of growing supermassive black holes are known to be luminous in radio wavelengths, which are referred to as radio-loud active galactic nuclei (AGNs). These radio-loud AGNs are expected to play important roles in the formation of massive galaxies by controlling the growth of galaxies via negative feedback from AGNs. In this topic, we will search for new radio-loud AGNs by combining large datasets in the optical (from Subaru HSC SSP) and radio (from JVLA, etc.) wavelengths, and the physical properties of these galaxies will be investigated via spectral energy distribution modeling
Contact
Michel Gonin
03/10/2024
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Thesis :
Funding :
89
Statistical Study of Giant Molecular Clouds in Galaxies
Domaines
Relativity/Astrophysics/Cosmology
Nuclear physics and Nuclear astrophysics
Type of internship
Expérimental et théorique Description
In this topic, we will utilize extensive imaging spectroscopy datasets of galaxies in the local universe, such as M83, to study a large number of giant molecular clouds (GMCs). GMCs are considered the birthplace of massive stars within galaxies. Our investigation will focus on the physical and chemical properties of GMCs using rich ALMA imaging spectroscopy data sets of various molecular lines to understand the underlying physical processes that govern their evolution. This, in turn, will provide insights into the regulatory mechanisms affecting the overall evolution of galaxies.
Contact
Michel Gonin
03/10/2024
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Thesis :
Funding :
90
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
02/10/2024
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Thesis :
Funding :
91
Looking for radio signals from the most powerful sources of cosmic particles in the Universe (black holes, neutron stars, …)
Domaines
High energy physics
Relativity/Astrophysics/Cosmology
Nuclear physics and Nuclear astrophysics
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
02/10/2024
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Thesis :
Funding :
92
High Energy Gamma-Ray Astronomy (neutron stars, black holes)
Domaines
High energy physics
Relativity/Astrophysics/Cosmology
Nuclear physics and Nuclear astrophysics
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
02/10/2024
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Thesis :
Funding :
93
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
02/10/2024
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Thesis :
Funding :
94
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
02/10/2024
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Thesis :
Funding :
95
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
02/10/2024
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Thesis :
Funding :
96
Cosmological Constraints from Lyman Alpha Forest using Hybrid Effective Field Theory
Domaines
Relativity/Astrophysics/Cosmology
Type of internship
Expérimental et théorique 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
02/10/2024
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Thesis :
Funding :
97
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
02/10/2024
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Thesis :
Funding :
98
Crystallization of nanomaterials: theory and simulation
Domaines
Condensed matter
Statistical physics
Soft matter
Physics of liquids
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Kinetic theory ; Diffusion ; Long-range interacting systems
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Théorique, numérique Description
Research overview
The formation of a crystal is triggered by the emergence of a nucleation core. Classical nucleation theory (CNT) is widely employed to discuss its nature and its origin. In CNT, the thermodynamically stable phase is always the one that grows first and its size is then driven by the free energy competition between how much it costs to build a liquid-crystal interface and the gain from growing the crystal. Yet, following Ostwald’s rule, another structure may emerge beforehand if it is closer in free energy to the mother phase. Then, structural and also chemical reorganizations happen during the growth. This multi-stage nucleation mechanism already appears in bulk systems but can be amplified in nanocrystal nucleation where surface effects and chemical reactivity are enhanced. For nanoscience to be inspired by the practical applications instead of still being driven by the synthesis possibilities, it is crucial to reach a better understanding of the unique crystallization mechanisms leading to nanocrystals.
Simulation project
Atomistic simulations will be performed to study crystallization of binary particles. Examples will be taken from well-studied materials including CuZr, NiAl, NaCl, Water... We will investigate the correlation between the thermodynamic conditions and the final nanoparticles. The goal is to ultimately better understand how nucleation theory is affected by downsizing to the nanometric scale.
Contact
Julien LAM
01/10/2024
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Thesis :
Funding :
99
Machine-learning approaches to model interatomic interactions
Domaines
Condensed matter
Statistical physics
Soft matter
Physics of liquids
Nonequilibrium statistical physics
Non-equilibrium Statistical Physics
Kinetic theory ; Diffusion ; Long-range interacting systems
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Théorique, numérique Description
Research overview
Materials can be studied using computer simulation which enables one to probe the motion of each constituent atoms and to build correlations between the macroscopic properties and the microscopic behaviors. On the one hand, traditional quantum mechanics methods provides particularly accurate results up to the electronic structure of the material. Yet, the drawback of this method concerns its computational cost which prevents from studying large system sizes and long time scales. On the other hand, effective potentials have been developed to mimic atomic interactions thereby reducing those issues. However, these potentials are often built to reproduce bulk properties of the materials and can hardly be employed to study some specific systems including interfaces and nanomaterials. In this context, a new class of interatomic potentials based on machine-learning algorithms is being developed to retain the accuracy of traditional quantum mechanics methods while being able to run simulations with larger system sizes and longer time scales.
Simulation project
Using computer simulations, the student will construct a database that should be representative of the different interactions occurring in a specific material. Machine-learning potentials based on the least-angle regression algorithm as well as neural network potentials will be trained and their accuracy will be studied as a function of the size and the complexity of the database.
Contact
Julien LAM
01/10/2024
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Thesis :
Funding :
100
Deformulation of complex glass-like materials through statistical analysis of Raman spectra
Domaines
Condensed matter
Statistical physics
Type of internship
Théorique, numérique Description
This internship proposes to develop an advanced method for analyzing Raman spectra to characterize complex materials, in particular glasses, using machine learning.
Contact
Olivier Rivoire
01/10/2024
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Thesis :
Funding :
101
Study of electronic processes in nitride LEDs by electro-emission microscopy
Domaines
Condensed matter
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
Although nitride LEDs are extremely efficient at low indium content (for blue emission) and low current densities, they suffer from drastic drops in efficiency when going out of theses regimes, partly due to an increase of Auger-Meitner processes. The aim of the proposed internship is to quantify Auger-Meitner processes in in operando nitride LEDs, using electro-emission microscopy. In particular, the role of the device microscopic structure will be investigated.
Contact
Mylène Sauty
01/10/2024
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Thesis :
Funding :
102
Dripping of a honeybee cluster, analogy to a complex fluid
Domaines
Biophysics
Soft matter
Physics of living systems
Non-equilibrium Statistical Physics
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
Collective motion is a fascinating observation where the ensemble of agents can be seen as a single living object that can deform, flow and merge. A wealth of approaches has been developed over the years to model such systems including discrete and continuous strategies. In this new project, we focus on an original system that has barely been studied in the frame of mechanics and not at all in terms of rheology: a honeybee cluster. When a colony divides, the queen bee and thousands of worker bees swarm out of the hive and form a cohesive structure similar to a liquid drop hanging on a wire. The intriguing apparent mechanical properties of bee crowds are reminiscent of cohesive grains, like wet sand. Unlike granular materials, bees are active and cognitive, each agent can intentionally adapt its own movements, in this perspective the system is a promising tool to tackle new questions in the field of cognitive active matter.
Based on preliminary experiments, the intern will measure the flowing of living bee clusters through a constriction and try to quantify its physical properties as a living material. This is an interdisciplinary project with interactions with complex fluids physics, numerical modeling, active matter and ethology.
Contact
Aurélie Dupont
27/09/2024
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Thesis :
Funding :
103
Information flow and polymer physics of gene activity
Domaines
Statistical physics
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
27/09/2024
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Thesis :
Funding :
104
Experimental study of the interplay between hydrodynamical and visual interactions in fish schools
Domaines
Biophysics
Physics of living systems
Hydrodynamics/Turbulence/Fluid mechanics
Type of internship
Expérimental Description
This project aims to investigate the mechanisms by which fish schools self-organize, focusing on the relative contributions of visual and hydrodynamic interactions. To explore these dynamics, the experimental study will involve placing fish in a controlled flow environment where their interactions can be manipulated and observed under different conditions. By introducing corridors with transparent walls, the natural hydrodynamic interactions will be disrupted, allowing to isolate and examine the role of visual cues in schooling behavior. The intern will be actively involved in designing the experimental setups, maintaining the flow conditions, and analyzing the behavioral data to draw meaningful conclusions about the interplay between visual and hydrodynamic interactions in fish schooling. Our project also implies numerical approaches of the social and hydrodynamical interactions which will allow fruitful discussions between real life and simulations.
Contact
Aurélie Dupont
27/09/2024
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Thesis :
Funding :
105
Inertial quantum 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
Developing a broadband, high-sensitivity accelerometer operating at cryogenic temperatures is a key challenge in many cutting-edge experimental physics domains, from quantum technologies (including near-field microscopy, quantum memories, etc.) to gravitational wave detection. To realize such a sensor, a promising approach is hybrid optomechanics, which couples quantum and mechanical degrees of freedom in a single physical system.
Rare-earth ion-doped crystals, known for their extremely narrow optical transitions at low temperature (~3K), exhibit natural optomechanical coupling through the piezospectroscopic sensitivity of the ion’s energy levels to mechanical stress. These crystals have recently emerged as strong candidates for quantum-enabled, low-temperature accelerometry, and we recently demonstrated continuous optical measurement of cryostat vibrations with such crystals, with an already promising sensitivity and bandwidth [1,2].
However, significant work is needed to obtain an ultra-sensitive, unidirectional and calibrated accelerometer.
During this internship, we will investigate the fundamental and technical limitations of the method (in terms of sensitivity and bandwidth in particular), using emulated or real vibrations. Additionally, we aim to extend the operational range to higher temperatures (up to 10K), which will be key for expanding the potential applications of our sensor
Contact
Anne Louchet-Chauvet
Laboratory : Institut Langevin - Ondes et Images - UMR7587
Team : Materials, Resonances, Interfaces
Team Website
Team : Materials, Resonances, Interfaces
Team Website
25/09/2024
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Thesis :
Funding :
106
Quantum imaging for sub-shot noise monitoring of optically-levitated nano-particles
Domaines
Quantum optics/Atomic physics/Laser
Condensed matter
Quantum information theory and quantum technologies
Quantum optics
Nanophysics, nanophotonics, 2D materials and van der Waals heterostructures,, surface physicss, new electronic states of matter
Type of internship
Expérimental Description
In optical levitation, a nanoparticle is trapped in vacuum using tightly focused light. The light produces a force akin to a mechanical spring and the system reduces to a simple mass-spring resonator with kHz oscillations. Despite its simplicity, a levitated object provides remarkable interactions between light and its motion that can be harnessed to display quantum properties. In that regard, the particle must be cooled down to its quantum ground state, which requires to monitor its motion with optimal precision. Typically, this is achieved using the classical light produced by a laser. Yet, lasers are intrinsically shot-noise limited, thus making cooling challenging. Recently, some works have emphasized that quantum light can outperform classical light. For instance, entangled photons can serve to suppress shot noise. A photon of the pair images a target (signal), while a second acts as a reference (idler). As shot noise identically affects both photons, it is suppressed from the signal by subtracting the idler.
During this internship, the candidate will experimentally harness entangled photons to perform sub-shot noise monitoring of levitated objects. He or she will develop an entangled-photon source, later on deployed on a levitation setup. To characterize the source, the student will visit the team of Pr. Molina in San Sebastian (Spain). Following the internship, he or she will be offered a PhD in cotutelle between Prs. Bachelard and Molina’s teams.
Contact
Nicolas Bachelard
Laboratory : Laboratoire Ondes et Matière d'Aquitaine - UMR 5798
Team : Nanophotonics Group
Team Website
Team : Nanophotonics Group
Team Website
11/09/2024
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Thesis :
Funding :