HAL : Dernières publications

[hal-03863641] Axisymmetric Shell Modelling of Viscoelastic Yeast Cells in the Finite Strain Range

ano.nymous@ccsd.cnrs.fr.invalid (Zeinab Awada) — Thu, 24 Nov 2022 11:21:40 +0000

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[hal-03054291] Quantifying the rationality of rhythmic signals

ano.nymous@ccsd.cnrs.fr.invalid (Alexandre Guillet) — Sat, 26 Nov 2022 08:33:55 +0000

Rhythms and vibrations represent the quintessence of life, they are ubiquitous (systemic) in all living systems. Recognising, unfolding these rhythms is paramount in medicine, for example in the physiology of the heart, lung, hearing, speech, brain, the cellular and molecular processes involved in biological clocks. The importance of the commensurability of the frequencies in different rhythms has been thoroughly studied in music. We define a log-frequency correlation measure on spectral densities that gives the distribution of frequency ratios (rational or irrational) in between two signals, and this measure is generalized to a time-log-frequency correlation measure using analytic wavelets. We illustrate these concepts on numerical signals (sums of sine functions) and voice recordings from the Voice-Icar-Federico II database. Finally, with a second correlation operation from two of these logfrequency correlation measures we introduce another measure that we call sonance, from which we can estimate the pitch transposition that would produce "harmony" (ratios of their harmonics being rational numbers) of two voices sung together.

[hal-03952671] Core–shell nanoheterodimers: laser-assisted deposition of single bimetallic Au@M (M = Au, Ag, Pd, Pt) nanodots on TiO₂ nanoparticles

ano.nymous@ccsd.cnrs.fr.invalid (Fenghuan Zhao) — Tue, 24 Jan 2023 04:06:01 +0000

We propose to synthesize well-controlled core-shell nanoheterodimers (NHDs) based on single bimetallic Au@M (M = Au, Ag, Pd, Pt) nanodots (BNDs) grown on bare TiO 2 nanoparticles (NPs) by a two-step laser-assisted deposition. The high photon flux emitted by a focused UV laser triggers nucleation and growth of a single core nanodot (ND) and its size is quantitatively controlled by varying the time exposure and the concentration of gold ions in the solution in the first step. A second laser deposition is performed after adding a new metal precursor to the Au-TiO 2 NHDs thus prepared. Due to the vectorial nature of the first Au-TiO 2 NHDs when photo-excited, and thus the subsequent efficient carrier separation, the second photodeposition strictly takes place on the first gold NDs. Growth is epitaxial for both

[hal-03694008] Nanoparticle Taylor dispersion near charged surfaces with an open boundary

ano.nymous@ccsd.cnrs.fr.invalid (Alexandre Vilquin) — Fri, 20 Jan 2023 03:33:40 +0000

The dispersive spreading of microscopic particles in shear flows is influenced both by advection and thermal motion. At the nanoscale, interactions between such particles and their confining boundaries become unavoidable. We address the roles of electrostatic repulsion and absorption on the spatial distribution and dispersion of charged nanoparticles in near-surface shear flows, observed under evanescent illumination. The electrostatic repulsion between particles and the lower charged surface is tuned by varying electrolyte concentrations. Particles leaving the field of vision can be neglected from further analysis, such that the experimental ensemble is equivalent to that of Taylor dispersion with absorption. These two ingredients modify the particle distribution, deviating strongly from the Gibbs-Boltzmann one at the nanoscale studied here. The overall effect is to restrain the accessible space available to particles, leading to a striking, ten-fold reduction in the spreading dynamics as compared to the non-interacting case.

[hal-03919921] Numerical simulation of universal morphogenesis of fluid interface deformations driven by radiation pressure

ano.nymous@ccsd.cnrs.fr.invalid (Hugo Chesneau) — Tue, 24 Jan 2023 04:02:22 +0000

We report on numerical simulation of fluid interface deformations induced either by acoustic or optical radiation pressure. This is done by solving simultaneously the scalar wave propagation equation and the two-phase flow equations using the boundary element method. Using dimensional analysis, we show that interface deformation morphogenesis is universal, i.e. depends on the same dimensionless parameters in acoustics and electromagnetics. We numerically investigate a few selected phenomena-in particular the shape of large deformations, the slenderness transition and its hysteresis-and compare with existing and novel experimental observations. Qualitative agreement between the numerical simulations and experiments is found when the mutual interaction between wave propagation and wave-induced deformations is taken into account. Our results demonstrate the leading role of the radiation pressure in morphogenesis of fluid interface deformations and the importance of the propagation-deformation interplay .

[hal-03892664] Mechanical response of a thick poroelastic gel in contactless colloidal-probe rheology

ano.nymous@ccsd.cnrs.fr.invalid (Caroline Kopecz-Muller) — Tue, 13 Dec 2022 09:48:39 +0000

When a rigid object approaches a soft material in a viscous fluid, hydrodynamic stresses arise in the lubricated contact region and deform the soft material. The elastic deformation modifies in turn the flow, hence generating a soft-lubrication coupling. Moreover, soft elastomers and gels are often porous. These materials may be filled with solvent or uncrosslinked polymer chains, and might be permeable to the surrounding fluid, which complexifies further the description. Here, we derive the point-force response of a semi-infinite and permeable poroelastic substrate. Then, we use this fundamental solution in order to address the specific poroelastic lubrication coupling associated with contactless colloidal-probe methods. In particular, we derive the conservative and dissipative components of the force associated with the oscillating vertical motion of a sphere close to the poroelastic substrate. Our results may be relevant for dynamic surface force apparatus and contactless colloidal-probe atomic force microscopy experiments on soft, living and/or fragile materials, such as swollen hydrogels and biological membranes.

[hal-03889405] On the bridge hypothesis in the glass transition of freestanding polymer films

ano.nymous@ccsd.cnrs.fr.invalid (Haggai Bonneau) — Thu, 05 Jan 2023 20:12:09 +0000

Freestanding thin polymer films with high molecular weights exhibit an anomalous decrease in the glass-transition temperature with film thickness. Specifically, in such materials, the measured glass-transition temperature evolves in an affine way with the film thickness, with a slope that weakly depends on the molecular weight. De Gennes proposed a sliding mechanism as the hypothetical dominant relaxation process in these systems, where stress kinks could propagate in a reptation-like fashion through so called bridges, i.e. from one free interface to the other along the backbones of polymer macromolecules. Here, by considering the exact statistics of finite-sized random walks within a confined box, we investigate in details the bridge hypothesis. We show that the sliding mechanism cannot reproduce the basic features appearing in the experiments, and we exhibit the fundamental reasons behind such a fact.

[hal-03887792] Specular reflection and transmission of electromagnetic waves by disordered metasurfaces

ano.nymous@ccsd.cnrs.fr.invalid (Kevin Vynck) — Wed, 28 Dec 2022 03:20:31 +0000

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[hal-03906476] Kinetics and wavelength dependence of thermal and gain lens induced in Nd:YAG rod amplifier

ano.nymous@ccsd.cnrs.fr.invalid (Martin Maillard) — Thu, 05 Jan 2023 03:20:17 +0000

Author Queries Please answer these queries by marking the required corrections at the appropriate point in the text or referring to the relevant line number in your PDF proof. Q1 The funding information for this article has been generated using the information you provided to us at the time of article submission. Please check it carefully. If any information needs to be corrected or added, please provide the full name of the funding organization/institution as provided in the Crossref Open Funder Registry (https://search.crossref.org/funding).

[hal-03713580] Non-Gaussian diffusion near surfaces

ano.nymous@ccsd.cnrs.fr.invalid (Arthur Alexandre) — Tue, 20 Dec 2022 03:58:18 +0000

We study the diffusion of particles confined close to a single wall and in double-wall planar channel geometries where the local diffusivities depend on the distance to the boundaries. Displacement parallel to the walls is Brownian as characterized by its variance, but it is non-Gaussian having a non-zero fourth cumulant. Establishing a link with Taylor dispersion, we calculate the fourth cumulant and the tails of the displacement distribution for general diffusivity tensors along with potentials generated by either the walls or externally, for instance gravity. Experimental and numerical studies of the motion of a colloid in the direction parallel to the wall give measured fourth cumulants which are correctly predicted by our theory. Interestingly, contrary to models of Brownian-yet-non-Gaussian diffusion, the tails of the displacement distribution are shown to be Gaussian rather than exponential. All together, our results provide additional tests and constraints for the inference of force maps and local transport properties near surfaces.

[hal-03872584] Drifting/Diffusive Regime Transition of Deformable Particles in a Honeycomb Network

ano.nymous@ccsd.cnrs.fr.invalid (Zaiyi Shen) — Tue, 17 Jan 2023 16:16:11 +0000

Transport of deformable particles in a honeycomb network is studied numerically. It is shown that the particle deformability has a strong impact on their distribution in the network. For sufficiently soft particles, we observe a short memory behavior from one bifurcation to the next, and the overall behavior consists in a random partition of particles, exhibiting a diffusion-like transport. On the contrary, stiff enough particles undergo a biased distribution whereby they follow a deterministic partition at bifurcations, leading to a lateral drift in the network. An increase of concentration enhances particle-particle interactions which shorten the memory effect, turning the particle lateral drift into an effective diffusion. We expect the drifting/diffusive regime transition to be generic for deformable particles.

[hal-03871719] Spin‐Orbit Modal Optical Vortex Beam Shaping from Dielectric Metasurfaces

ano.nymous@ccsd.cnrs.fr.invalid (Mingke Jin) — Fri, 09 Dec 2022 03:20:24 +0000

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[hal-03863984] Inhibition of membrane repair protein annexin-A2 prevents tumor invasion and metastasis

ano.nymous@ccsd.cnrs.fr.invalid (Céline Gounou) — Thu, 05 Jan 2023 15:08:06 +0000

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[hal-03864020] Annexin-A5 and annexin-A6 silencing prevents metastasis of breast

ano.nymous@ccsd.cnrs.fr.invalid (Céline Gounou) — Thu, 05 Jan 2023 15:08:06 +0000

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[hal-03763969] Dynamical scaling as a signature of multiple phase competition in Yb 2 Ti 2 O 7

ano.nymous@ccsd.cnrs.fr.invalid (Allen Scheie) — Wed, 16 Nov 2022 03:52:42 +0000

Yb2Ti2O7 is a celebrated example of a pyrochlore magnet with highly frustrated, anisotropic exchange interactions. To date, attention has largely focused on its unusual, static properties, many of which can be understood as coming from the competition between different types of magnetic order. Here we use inelastic neutron scattering with exceptionally high energy resolution to explore the dynamical properties of Yb2Ti2O7. We find that spin correlations exhibit dynamical scaling, analogous to behavior found near to a quantum critical point. We show that the observed scaling collapse can be explained within a phenomenological theory of multiple-phase competition, and confirm that a scaling collapse is also seen in semiclassical simulations of a microscopic model of Yb2Ti2O7. These results suggest that dynamical scaling may be general to systems with competing ground states.

[hal-03854416] Mesoscopic Klein-Schwinger effect in graphene

ano.nymous@ccsd.cnrs.fr.invalid (Aurélien Schmitt) — Tue, 06 Dec 2022 04:08:00 +0000

Strong electric field annihilation by particle-antiparticle pair creation, described in detail by Sauter and Schwinger, is a basic non-perturbative prediction of quantum electrodynamics. Its experimental demonstration remains elusive as Schwinger fields E S are beyond reach even for the light electron-positron pairs. Here we put forward a mesoscopic variant of the Schwinger effect in graphene, which hosts Dirac fermions with electron-hole symmetry. Using DC transport and RF noise, we report on universal 1d-Schwinger conductance at the pinch-off of ballistic graphene transistors. Strong pinch-off electric fields are concentrated in a length Λ > ∼ 0.1 µm at the transistor drain, and induce Schwinger e-h pair creation at saturation, for a Schwinger voltage V S = E S Λ on the order of the pinch-off voltage. This Klein-Schwinger effect (KSE) precedes an instability toward an ohmic Zener regime, which is rejected at twice the pinch-off voltage in long devices. The KSE not only gives clues to current saturation limits in ballistic graphene, but also opens new routes for quantum electrodynamic experiments in the laboratory.

[hal-03848448] Mechanical characterization of core-shell microcapsules

ano.nymous@ccsd.cnrs.fr.invalid (Kaili Xie) — Wed, 16 Nov 2022 03:52:43 +0000

Core-shell configurations are ubiquitous in nature such as in the form of bacterial and cells. Inspired by this, microcapsules are designed with actives as the cores surrounded by thin shells. They not only play an increasing role as artificial models for understanding dynamic behaviors of biological cells in flows, but are also becoming a fundamental class of artificial vehicles at the heart of drug delivery and release in applications. The mechanical properties of the shells are of great importance in this context. Here, we review recent experimental and theoretical characterizations of microcapsules, focusing on the soft and deformable particles with liquid cores. We begin by exploring the concept and fabrication of artificial microcapsules, followed by a discussion of different methods on the mechanical characterization of the shell.

[hal-03843477] Surface and Bulk Relaxation of Vapour-Deposited Polystyrene Glasses

ano.nymous@ccsd.cnrs.fr.invalid (Junjie Yin) — Mon, 14 Nov 2022 14:40:22 +0000

We have studied the liquid-like response of the surface of vapour-deposited glassy films of polystyrene to the introduction of gold nanoparticles on the surface. The build-up of polymer material was measured as a function of time and temperature for both as-deposited films, as well as films that have been rejuvenated to become normal glasses cooled from the equilibrium liquid. The temporal evolution of the surface profile is well described by the characteristic power law of capillary-driven surface flows. In all cases, the surface evolution of the as-deposited films and the rejuvenated films are enhanced compared to bulk and are not easily distinguishable from each other. The temperature dependence of the measured relaxation times determined from the surface evolution is found to be quantitatively comparable to similar studies for high molecular weight spincast polystyrene. Comparisons to numerical solutions of the glassy thin film equation provide quantitative estimates of the surface mobility. For temperatures sufficiently close to the glass-transition temperature, particle embedding is also measured and used as a probe of bulk dynamics, and in particular bulk viscosity.

[hal-03871659] Observation of Polarization Singularities and Topological Textures in Sound Waves

ano.nymous@ccsd.cnrs.fr.invalid (Ruben Muelas-Hurtado) — Thu, 08 Dec 2022 08:32:53 +0000

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[hal-03832770] Numerical simulations of confined Brownian motion

ano.nymous@ccsd.cnrs.fr.invalid (Elodie Millan) — Sat, 29 Oct 2022 03:55:45 +0000

Brownian motion is a central scientific paradigm. Recently, due to increasing efforts and interests towards miniaturization and small-scale physics or biology, the effects of confinement on such a motion have become a key topic of investigation. Essentially, when confined near a wall, a particle moves much slower than in the bulk due to friction at the boundaries. The mobility is therefore locally hindered and space-dependent, which in turn leads to the apparition of so-called multiplicative noises. Here, we present efficient, broadrange and quantitative numerical simulations of a such a problem. Specifically, we integrate the overdamped Langevin equation governing the thermal dynamics of a negatively-buoyant spherical colloid within a viscous fluid confined by rigid walls, including surface charges. From the produced large set of long random trajectories, we perform a complete statistical analysis and extract all the key quantities, such as the probability distributions in displacements and their first moments. In particular, we propose a convenient method to compute high-order cumulants by reducing convergence problems, and employ it to characterize the inherent non-Gaussianity of the process.

[hal-03810529] Exact solutions for viscous Marangoni spreading

ano.nymous@ccsd.cnrs.fr.invalid (Thomas Bickel) — Tue, 08 Nov 2022 03:20:01 +0000

When surface-active molecules are released at a liquid interface, their spreading dynamics is controlled by Marangoni flows. Though such Marangoni spreading was investigated in different limits, exact solutions remain very few. Here we consider the spreading of an insoluble surfactant along the interface of a deep fluid layer. For two-dimensional Stokes flows, it was recently shown that the non-linear transport problem can be exactly mapped to a complex Burgers equation [Crowdy, SIAM J. Appl. Math., 81, 2526 (2021)]. We first present a very simple derivation of this equation. We then provide fully explicit solutions and find that varying the initial surfactant distribution-pulse, hole, or periodic-results in distinct spreading behaviors. By obtaining the fundamental solution, we also discuss the influence of surface diffusion. We identify situations where spreading can be described as an effective diffusion process but observe that this approximation is not generally valid. Finally, the case of a three-dimensional flow with axial symmetry is briefly considered. Our findings should provide reference solutions for Marangoni spreading, that may be tested experimentally with fluorescent or photoswitchable surfactants.

[hal-03685227] Schwinger boson theory of the J1,J2=J3 kagome antiferromagnet

ano.nymous@ccsd.cnrs.fr.invalid (Tristan Lugan) — Thu, 13 Oct 2022 03:47:59 +0000

We study the kagome antiferromagnet for quantum spin-1/2 with first J1, second J2 and third J3 neighbour exchanges, along the J2 = J3 = J line. We use Schwinger-boson mean-field theory for the precise determination of the phase diagram, and two different rewritings of the Hamiltonian to build an intuition about the origin of the transitions. The spin liquid obtained at J = 0 remains essentially stable over a large window, up to J = 1/3, because it is only weakly frustrated by the J term. Then at J = 1/2, the intermediate Z2 spin liquid condenses into a long-range chiral order because of the change of nature of local magnetic fluctuations. As a side benefit, our Hamiltonian rewriting offers an exact solution for the ground state of our model on a Husimi cactus.

[hal-03863624] Experimental measurement of heat transport property: Why is heat transport modelling required for nanometrology?

ano.nymous@ccsd.cnrs.fr.invalid (Séverine Gomés) — Thu, 24 Nov 2022 15:05:57 +0000

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[hal-03809735] Effective temperature and dissipation of a gas of active particles probed by the vibrations of a flexible membrane

ano.nymous@ccsd.cnrs.fr.invalid (Jean François Boudet) — Thu, 13 Oct 2022 03:17:29 +0000

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[hal-03696161] Microscopic foundation of the $\mu$(I) rheology for dense granular flows on inclined planes.

ano.nymous@ccsd.cnrs.fr.invalid (Denis Dumont) — Thu, 06 Oct 2022 03:56:08 +0000

Macroscopic and microscopic properties of dense granular layers flowing down inclined planes are obtained from Discrete-Element-Method simulations for both frictionless and frictional grains. Three fundamental observations for dense granular flows are recovered, namely the occurrence of a critical stress, the Bagnold velocity profile, as well as well-defined friction and dilatancy laws. The microscopic aspects of the grain motion highlight the formation of transient clusters. From this microscopic picture, we derive a theoretical scaling model without any empirical input that explains quantitatively the fundamental laws of dense granular flows in incline plane and shear geometries. The adequacy between the model and the observed results suggests that granular flows can be viewed as flows from thermal fluids of hard spheres.

[hal-03810977] Influence of Generated Defects by Ar Implantation on the Thermoelectric Properties of ScN

ano.nymous@ccsd.cnrs.fr.invalid (Razvan Burcea) — Thu, 22 Dec 2022 03:57:36 +0000

Nowadays, making thermoelectric materials more efficient in energy conversion is still a challenge. In this work, to reduce the thermal conductivity and thus improve the overall thermoelectric performances, point and extended defects were generated in epitaxial 111-ScN thin films by implantation using argon ions. The films were investigated by structural, optical, electrical, and thermoelectric characterization methods. The results demonstrated that argon implantation leads to the formation of stable defects (up to 750 K operating temperature). These were identified as interstitial-type defect clusters and argon vacancy complexes. The insertion of these specific defects induces acceptor-type deep levels in the band gap, yielding a reduction in the free-carrier mobility. With a reduced electrical conductivity, the irradiated sample exhibited a higher Seebeck coefficient while maintaining the power factor of the film. The thermal conductivity is strongly reduced from 12 to 3 W·m–1·K–1 at 300 K, showing the influence of defects in increasing phonon scattering. Subsequent high-temperature annealing at 1573 K leads to the progressive evolution of these defects: the initial clusters of interstitials evolved to the benefit of smaller clusters and the formation of bubbles. Thus, the number of free carriers, the resistivity, and the Seebeck coefficient are almost restored but the mobility of the carriers remains low and a 30% drop in thermal conductivity is still effective (ktotal ∼ 8.5 W·m–1·K–1). This study shows that control defect engineering with defects introduced by irradiation using noble gases in a thermoelectric coating can be an attractive method to enhance the figure of merit of thermoelectric materials.

[hal-03863674] Why is heat transport modelling required for nanometrology?

ano.nymous@ccsd.cnrs.fr.invalid (Séverine Gomés) — Fri, 16 Dec 2022 04:02:58 +0000

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[hal-03788404] Activity Induced Rigidity of Liquid Droplets

ano.nymous@ccsd.cnrs.fr.invalid (Kaili Xie) — Thu, 29 Sep 2022 05:02:56 +0000

Here we show that encapsulating active Janus particles within a drop renders it more resistant to deformation. This drop is deformed under the action of an extensional flow. Such deformation is primarily resisted by the drop interfacial tension. When the particles are active under the action of Laser illumination, the deformation decreases signalling an increase in effective tension or Laplace pressure. This increase is attributed to the activity of the particles. Our results using numerous drop sizes, particle number densities and active velocities show that the obtained increase agrees surprisingly well, over an extended range, with a standard expression for the pressure engendered by an ensemble of active particles, proposed years ago but not tested yet in three dimensions.

[tel-03813782] Dispersion dans les milieux hétérogènes : une étude des effets hydrodynamiques et de la diffusion médiée par la surface.

ano.nymous@ccsd.cnrs.fr.invalid (Arthur Alexandre) — Fri, 14 Oct 2022 03:25:49 +0000

Cette thèse a pour objet l'étude de la dispersion, c'est à dire la vitesse d'étalement de particules traceurs, dans des milieux hétérogènes, présentant une périodicité spatiale. Ce processus se quantifie par un coefficient de diffusivité effective. Il est bien connu que la présence de parois ou d'obstacles diminue la dispersion, tandis qu'un écoulement de cisaillement a pour effet de l'augmenter. Cependant, la plupart des études considèrent des parois parfaitement réfléchissantes. Dans un premier chapitre, nous dérivons une expression générale de la diffusivité effective pour un modèle de diffusion médiée par la surface qui inclut la possibilité pour les particules d'adhérer et de diffuser sur les parois. En appliquant cette formule à deux systèmes (un réseau d'obstacles sphériques et un canal périodique), nous montrons que ce mécanisme d'adhésion permet d'augmenter la dispersion par rapport au cas de parois réfléchissantes, et ce même si la diffusion à la surface est plus lente que dans le volume. Dans un deuxième temps, nous examinons les effets combinés d'un écoulement visqueux et du confinement sur la dispersion dans un canal ondulé. Nous mettons en évidence à l'aide d'expressions analytiques la compétition entre ces deux effets antagonistes dans la limite de faibles ondulations des parois. Dans la limite opposée, les fortes ondulations des parois ont pour effet de piéger les particules traceurs. Nous mettons en évidence à l'aide de l'expression de la diffusivité une équivalence avec un problème de dispersion de Taylor dans un canal uniforme dont les parois sont partiellement adsorbantes. Dans un troisième temps, nous prenons en compte simultanément l'ondulation des parois, l'écoulement visqueux ainsi que la possibilité d'adhésion aux surfaces. En dérivant un formalisme général, nous montrons que la combinaison de ces trois paramètres induit des effets non-triviaux sur la dispersion. Dans un dernier chapitre, nous nous intéressons à la dynamique d'une particule Brownienne confinée dans un canal plat. Nous dérivons une expression généralisée de la diffusivité de Taylor en exprimant le deuxième cumulant. De même, nous quantifions la non-gaussianité de la distribution en position suivant l'axe du canal en étudiant analytiquement les cumulants d'ordres supérieurs.

[hal-03781137] Rotation Control, Interlocking, and Self‐Positioning of Active Cogwheels

ano.nymous@ccsd.cnrs.fr.invalid (Quentin Martinet) — Wed, 30 Nov 2022 11:22:07 +0000

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[hal-03776303] Everlasting impact of initial perturbations on first-passage times of non-Markovian random walks

ano.nymous@ccsd.cnrs.fr.invalid (N. Levernier) — Thu, 22 Sep 2022 14:11:09 +0000

Persistence, defined as the probability that a signal has not reached a threshold up to a given observation time, plays a crucial role in the theory of random processes. Often, persistence decays algebraically with time with non trivial exponents. However, general analytical methods to calculate persistence exponents cannot be applied to the ubiquitous case of non-Markovian systems relaxing transiently after an imposed initial perturbation. Here, we introduce a theoretical framework that enables the non-perturbative determination of persistence exponents of Gaussian non-Markovian processes with non stationary dynamics relaxing to a steady state after an initial perturbation. Two situations are analyzed: either the system is subjected to a temperature quench at initial time, or its past trajectory is assumed to have been observed and thus known. Our theory covers the case of spatial dimension higher than one, opening the way to characterize non-trivial reaction kinetics for complex systems with non-equilibrium initial conditions.

[hal-03617124] Frustration on a centred pyrochlore lattice in metal-organic frameworks

ano.nymous@ccsd.cnrs.fr.invalid (Rajah Nutakki) — Wed, 31 Aug 2022 11:49:46 +0000

Geometric frustration inhibits magnetic systems from ordering, opening a window beyond Landau's paradigm into topological matter and emergent gauge fields, with potential applications to quantum computing. In most systems frustration stems from one of only two elementary units of spins: either triangles or tetrahedra. Here we explore an alternative route for frustration via molecular design in the metal-azolate framework [Mn(II)(ta)2], whose units are centred tetrahedra made of five spins. Despite a Curie-Weiss temperature of -21 K indicating the energy scale of magnetic interactions, [Mn(II)(ta)2] orders only at 0.43 K, putting it firmly in the category of highly frustrated magnets. Using a combination of simulations and field theory, we show that this material is proximate to a spin liquid described as a three-dimensional "slab" of a four-dimensional emergent electric field. The large degeneracy and robustness of this spin liquid, and additional chemical possibilities in the metal-organic frameworks beyond the pyrochlore structure, unlock a new door in frustrated magnetism.

[hal-03763970] Observing Magnetic Monopoles in Spin Ice using Electron Holography

ano.nymous@ccsd.cnrs.fr.invalid (Ankur Dhar) — Thu, 01 Sep 2022 03:17:11 +0000

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[hal-03302160] Structural magnetic glassiness in spin ice Dy_2Ti_2O_7

ano.nymous@ccsd.cnrs.fr.invalid (Anjana M. Samarakoon) — Wed, 31 Aug 2022 11:48:07 +0000

The origin and nature of glassy dynamics presents one of the central enigmas of condensed-matter physics across a broad range of systems ranging from window glass to spin glasses. The spin-ice compound Dy2Ti2O7, which is perhaps best known as hosting a three-dimensional Coulomb spin liquid with magnetically charged monopole excitations, also falls out of equilibrium at low temperature. How and why it does so remains an open question. Based on an analysis of low-temperature diffuse neutron-scattering experiments employing different cooling protocols alongside recent magnetic noise studies, combined with extensive numerical modeling, we argue that upon cooling, the spins freeze into what may be termed a “structural magnetic glass,” without an a priori need for chemical or structural disorder. Specifically, our model indicates the presence of frustration on two levels, first producing a near-degenerate constrained manifold inside which phase ordering kinetics is in turn frustrated. A remarkable feature is that monopoles act as sole annealers of the spin network and their pathways and history encode the development of glass dynamics, allowing the glass formation to be visualized. Our results suggest that spin ice Dy2Ti2O7 provides one prototype of magnetic glass formation specifically and a setting for the study of kinetically constrained systems more generally.

[hal-03707419] Droplet impacts on cold surfaces

ano.nymous@ccsd.cnrs.fr.invalid (B. Gorin) — Fri, 01 Jul 2022 08:44:02 +0000

We study drop impact for the case where the impacted surface is cooled below the freezing temperature of the liquid droplet. The freezing is found to affect the spreading dynamics of the impacting drops and, thus, the degree of surface coverage. The cooling of the surface leads to the arrest of the three-phase contact line, impeding droplet spreading and, thus, drastically reducing the maximum spreading diameter. Besides the surface temperature, the impact speed is also an important parameter: the higher the impact speed, the more the droplet spreads before arrest. Based on experimental observations of droplet impacts using two different liquids and two different substrates, we show using a combination of experiments and a one-dimensional freezing model, that droplet arrest occurs when a solid layer of the liquid forms on the substrate: droplet arrest occurs when this solid layer reaches a well-defined critical thickness. We then devise a simple model that efficiently predicts the maximum spreading diameter of droplets impinging, at different velocities, and freezing onto surfaces maintained at different temperatures below the liquid freezing point.

[hal-03871587] Optical cloaking of macroscopic objects by geometric-phase vortex processing

ano.nymous@ccsd.cnrs.fr.invalid (Mushegh Rafayelyan) — Thu, 08 Dec 2022 14:55:02 +0000

Abstract We report on free-space strategy for electromagnetic concealment of three-dimensional macroscopic objects in the optical domain owing to unique energy flow redirection capabilities enabled by optical phase singularities. We propose and implement the generation of a quasi-nodal volume based on optical vortex Fourier processing, which inhibits light scattering from objects placed inside. The proof of concept is made by numerical simulations and the experimental implementation is carried out in the visible domain by using geometric phase vortex phase masks. Optical cloaking demonstration is made by using stainless steel sphere as the object to be concealed. The geometric phase nature of the vortex masks confers polarization independent features to the device and makes it possible to implement in a reflection mode.

[hal-03719127] Lift at low Reynolds number

ano.nymous@ccsd.cnrs.fr.invalid (Lionel Bureau) — Fri, 22 Jul 2022 03:10:13 +0000

Lift forces are widespread in hydrodynamics. These are typically observed for big and fast objects, and are often associated with a combination of fluid inertia (\textit{i.e.} large Reynolds numbers) and some specific symmetry-breaking mechanism. In contrast, low-Reynolds-number flows are usually overdamped and do not exhibit such peculiar and interesting features. However, the inclusion of boundary effects qualitatively changes this picture. Indeed, in the context of soft and biological matter, recent studies have revealed the emergence of novel lift forces generated by boundary softness, flow gradients and/or surface charges. The aim of the present review is to gather and analyse this corpus of literature, in order to identify and unify the questioning within the associated communities, and pave the way towards future research around lift effects at low Reynolds numbers.

[tel-03772522] Charge-Transfer Chemical Reactions and Chiral Discrimination in Electromagnetic Fabry-Pérot Cavities

ano.nymous@ccsd.cnrs.fr.invalid (Lorenzo Mauro) — Fri, 09 Sep 2022 03:21:59 +0000

The first part of the thesis concerns an investigation on the chemical reactivity of molecular populationsconfined inside a nanofluidic Fabry-Pérot cavity. Due to strong light-matter interactions developing betweena resonant electromagnetic cavity mode and the electric dipole moment of the confined molecules, a collectivePolariton excitation is formed. The former gets dressed by environmental vibrational and rotational degreesof freedom of the solvent. We call the resulting Polariton dressed by its cloud of environmental excitationa “Reacton”, since it further undergoes chemical reactions. We characterize how the Reacton formationmodifies the kinetics of a photoisomerization chemical reaction involving an elementary charge-transfer pro-cess. We show that the reaction driving force and reorganization energy are both modulated optically bythe reactant concentration, the vacuum Rabi splitting, and the detuning between the Fabry-Pérot cavityfrequency and targeted electronic transition. Finally, by computing the ultrafast picosecond dynamics of thewhole photochemical reaction, we predict that, despite optical cavity losses and solvent-mediated nonradia-tive relaxation, measurable signatures of the reacton formation can be found in state-of-the-art pump-probeexperiments.The second part focuses on the chiral discrimination in Fabry-Pérot cavities. A Fabry-Pérot interferometerfilled with chiral molecules has a well defined Differential Circular Transmission (DCT) signal under normalillumination of circularly polarized light. Based on this figure of merit, we firstly provide analytical andnumerical evidence that traditional Fabry-Pérot interferometers cannot enhance the chiroptical response ofmolecules, because the mirrors perfectly convert the circular polarization of light rays. We hence proposeand model an helicity-preserving cavity, with chiral mirrors, satisfying time-reversal symmetry. The emptycavity, made by the modelled chiral mirrors, generates a spectral helicity-preserving region which is notavailable with a traditional interferometer. The region breaks, in a small frequency range, the perfectinternal conversion of polarized light and thus it enables to discriminate the otherwise achiral cavity lightmodes. Polaritons which are generated at resonance with the preserving region thus inheritates a partialchiral character. By subtracting the helicity-preserving cavity contribution to the total DCT, we show thatour proposed setup is up to two orders of magnitude more sensitive with respect to the chiroptical responseof the isolated molecules. We reveal that the registered enhancement is consistent even for an extremelyweak molecular chiroptical responses, and that our setup can enhance the chiral signal of molecules either inthe weak or in the strong coupling (Polaritonic) regime.

[hal-03633285] Giant Diffusion of Nanomechanical Rotors in a Tilted Washboard Potential

ano.nymous@ccsd.cnrs.fr.invalid (Louis Bellando) — Wed, 20 Jul 2022 03:48:04 +0000

We present an experimental realization of a biased optical periodic potential in the low friction limit. The noise-induced bistability between locked (torsional) and running (spinning) states in the rotational motion of a nanodumbbell is driven by an elliptically polarized light beam tilting the angular potential. By varying the gas pressure around the point of maximum intermittency, the rotational effective diffusion coefficient increases by more than 3 orders of magnitude over freespace diffusion. These experimental results are in agreement with a simple two-state model that is derived from the Langevin equation through using timescale separation. Our work provides a new experimental platform to study the weak thermal noise limit for diffusion in this system.

[hal-03376419] Structural characterization of the interfacial self-assembly of chitosan with oppositely charged surfactant

ano.nymous@ccsd.cnrs.fr.invalid (Revaz Chachanidzea) — Thu, 23 Jun 2022 09:44:49 +0000

Controlling the assembly of colloids at liquid-liquid interfaces offers new ways to fabricate soft materials with specific physical properties. However, little is known of the relationships between the kinetics of interfacial assembly, structural and rheological properties of such interfaces. We studied the kinetics of the assembly of two oppositely charged polyelectrolytes using a multi-scale approach. Soft interfaces were formed from the complexation at water-oil interface of chitosan, a polysaccharide carrying positively charged groups, and a fatty acid exhibiting negative charges. The growth kinetics of the membrane was followed by interfacial rheometry and space- and time- resolved dynamic light scattering. This set of techniques revealed that the interfacial complexation was a multi-step process. At short time-scale, the interface was fluid and made of heterogeneous patches. At a gelation time, the surface elastic modulus and the correlation between speckles increased sharply meaning that the patches percolated. Confocal and electron microscopy confirmed this picture, and revealed that the basic brick of the membrane was sub-micrometric aggregates of polyelectrolytes.

[hal-03863814] Two-layers cell-wall modelling for S. cerevisiae yeast

ano.nymous@ccsd.cnrs.fr.invalid (Zeinab Awada) — Mon, 05 Dec 2022 11:07:37 +0000

From human prehistory to present days, Saccharomyces cerevisiae yeasts exist in a wide range of daily use products. Biological studies on this kind of cells have provided a well-developped knowledge of its genetics and molecular properties. On another hand, the investigations on the mechanical properties were limited until only recently. For instance, experimental analyses show that the elastic modulus reported from the whole cell compression by micromanipulation is two orders of magnitude greater than that obtained using atomic force microscopy (AFM), e.g. [1, 2]. Here we assume that the diﬀerence is due to the heterogeneous nature of the cell-wall made of components with sensitively diﬀerent mechanical properties. The cell-wall is represented as a two-layers material; a soft outer layer mainly made of components with low mechanical properties identiﬁed by nanoindentation and a stiﬀer inner one where characteristics of the components are obtained from micromanipulation. Based on the Reissner-Mindlin’s shell kinematics, a viscoelastic model is developped. The ﬁnite strain range is adopted because of the soft nature of the cells. The deformation gradient is multiplicatively split into an elastically relaxing and a viscous parts. Furthermore, the incompressible inner ﬂuid of the closed cell is taken into account using follower loads the magnitude of which is continuously controled with the help of an Uzawa-like algorithm. In addition to the theoretical approach, a nanoindentation and micromanipulation test campaign is carried out on yeasts issued from the same culture with various speeds of loading. A mechanical interpretation is given to identify the viscoelastic properties of each layer and shows that these two techniques are complementary for a better characterization of the cell-wall. Within the ﬁnite element analysis, numerical simulations with the identiﬁed parameters show the time-dependent response of the whole cell.

[hal-03685547] How stickiness can speed up diffusion in confined systems

ano.nymous@ccsd.cnrs.fr.invalid (A. Alexandre) — Fri, 10 Jun 2022 03:35:26 +0000

The paradigmatic model for heterogeneous media used in diffusion studies is built from reflecting obstacles and surfaces. It is well known that the crowding effect produced by these reflecting surfaces slows the dispersion of Brownian tracers. Here, using a general adsorption desorption model with surface diffusion, we show analytically that making surfaces or obstacles attractive can accelerate dispersion. In particular, we show that this enhancement of diffusion can exist even when the surface diffusion constant is smaller than that in the bulk. Even more remarkably, this enhancement effect occurs when the effective diffusion constant, when restricted to surfaces only, is lower than the effective diffusivity with purely reflecting boundaries. We give analytical formulas for this intriguing effect in periodic arrays of spheres as well as undulating micro-channels. Our results are confirmed by numerical calculations and Monte Carlo simulations.

[tel-03813680] Revisiting statistical physics tools for the complex time-frequency characterization of physiological signals

ano.nymous@ccsd.cnrs.fr.invalid (Alexandre Guillet) — Mon, 28 Nov 2022 15:52:08 +0000

An analytical tool for the observation of the dynamics of living organisms is developed in this thesis, and applied to the study of interactions between the cardiac, respiratory and neural systems based on human recordings during sleep. These physiological signals are peculiar and complex: each recording is unique, non-stationary and cannot be reproduced. To solve this issue, a time-frequency analysis of physiological signals, based on analytic wavelets also called ``time-frequency atoms'', is proposed. The first part A of this thesis introduces this formalism, highlighting the adequacy of the log-normal wavelet in that context, the importance of the associated quality factor Q and its correspondence with the Heisenberg uncertainty principle. Extending this approach to the estimation of the time-frequency coherence of physiological signals, we separate temporal from spectral resolutions in order to introduce statistical degrees of freedom in this analysis. To assist the observation of physiological interactions between different sources, we define a generic family of complex rate estimators capturing both the modulations of the instantaneous frequency and amplitude, in a spectral band of interest. The second part B illustrates this methodology on physiological signals from polysomnography databases. The rich specificities of fluctuating rhythms contained in electrocardiograms (ECG), breathing signals and electroencephalograms (EEG) are thoroughly discussed to validate the generic estimation of the time-frequency coherence between pairs of recordings or their rate transformations. We compare the effectiveness of wide-band and narrow-band estimators in retrieving heart rate modulations, relative to a reference extraction method. From coherent cardiac and respiratory modulations, we observe three distinct scales of interaction: a fast one at the fundamental breathing frequency (RSA), a slow and less rhythmic one and an even slower one, regulating cardio-respiratory rates. In the wavelet framework, we propose an original time-dependent representation of the frequency ratios of cardiac and breathing rhythms that turns out very effective for tracking signatures of sleep apnea, rapid eye movement (REM) phases, and deep sleep stages. This approach of the cardio-respiratory coupling also offers a new perspective to detect synchronization episodes of cardio-respiratory coupling and their temporal fluctuations. The neural activity during sleep is introduced from the time-frequency analysis of EEG signals, and their characteristic sequences of multi-band power density and coherence patterns. Finally, we gather cardio-respiratory rates and neural magnitude signals and compare them in pairs in terms of time-frequency coherence. From an extensive analysis of 2650 recordings from a large polysomnography database, we point out the increased amplitude and coherence of slow apneic modulations, systematically emerging as a spectra l peak as compared to a flat baseline without apnea. We also show that apnea is concomitant with a strong coherence reduction of the fast RSA cardio-respiratory interaction and the very slow neuro-respiratory interaction. This study paves the way to new developments, outlined in the end of this thesis, such as the detection of sleep spindles from the phase of the sigma EEG band, and the coherence of their amplitude with slow delta oscillations during deep sleep.

[hal-03653650] Profil d'un câble tracté

ano.nymous@ccsd.cnrs.fr.invalid (Simon Villain-Guillot) — Tue, 03 May 2022 03:46:05 +0000

[...]

[hal-03686607] Design, elaboration and characterization of an immunosensor for the detection of a fungal toxin in foodstuffs analyses

ano.nymous@ccsd.cnrs.fr.invalid (Zeineb Benabdallah) — Fri, 03 Jun 2022 03:40:16 +0000

[...]

[hal-03495457] Femtosecond OPO pumped by a high power ytterbium rod-type fiber laser mode locked at harmonic repetition rates

ano.nymous@ccsd.cnrs.fr.invalid (Eric Freysz) — Sun, 26 Jun 2022 03:27:43 +0000

We report on an optical parametric oscillator (OPO) pumped by femtosecond pulses delivered by a large-mode-area, ytterbium-doped, rod-type fiber laser. This femtosecond laser that is mode locked at harmonic repetition rates of 108 MHz, 216 MHz, and 324 MHz provides an average output power of more than 4.5 W and tens of nJ per pulse. The repetition rate is changed by adjusting the pulse polarization inside the laser cavity. Remarkably, at all these repetition rates and without any modification to the cavity, the OPO delivers femtosecond signal pulses that are tunable from 1450 nm to 1700 nm, with an average output power higher than 1 W. Increasing the pump power of the rod-type fiber and decreasing the transmission of the OPO output coupler, we were able to run the OPO at 540 MHz.

[hal-03764767] Design, Elaboration, and Characterization of an Immunosensor for the Detection of a Fungal Toxin in Foodstuff Analyses

ano.nymous@ccsd.cnrs.fr.invalid (Zeineb Ben Abdallah) — Wed, 31 Aug 2022 03:14:27 +0000

This work describes the complete elaboration of an immunosensor for the detection of the fungal B1 aflatoxin (AFB1). In a first step, a system made of three screen-printed electrodes (SPEs) was manufactured using gold, silver/silver chloride, and carbon pastes. Raman spectroscopy showed that the thermal treatment applied to the electrodes enabled a strong decrease in the amount of undesirable organic molecules for each paste. Atomic Force Microscopy was also used to reveal the morphology of the electrode surfaces. In a second step, an autonomous and cheap electronic system was designed for the control of the sensor and electrochemical measurements, showing current variations significantly higher than those observed with a commercial system. In a last step, the gold working electrode of this system was functionalized by a simple self-assembly method, optimized in a previous work, with a molecular architecture including an antibody recognizing specifically AFB1. The complete device was finally realized by combining the SPEs and the electronic platform. The resulting setup was able to detect AFB1 toxin in a buffer with an LOD of about 50 fg/mL. It was then applied to the detection of AFB1 in rice milk, a more realistic medium comparable with those met in an agrifood context. The electrochemical detection of AFB1 was possible in a range of concentration between 0.5 pg/mL and 2.5 pg/mL, with the sensor behaving linearly in this range.

[tel-03717655] Lattice coherence and local non-local duality in f-electron materials

ano.nymous@ccsd.cnrs.fr.invalid (Bishal Poudel) — Sat, 09 Jul 2022 03:26:34 +0000

In this thesis, we will study f-electron systems under two different aspects: the formation and the breakdown of lattice coherence, and the nature of f-electrons, which can be either localized, itinerant, or dual. In the first part, we study lattice coherence in 4f systems with the atomic substitution of magnetic atoms by non-magnetic atoms. We will deal with the substitutional disorder by using the dynamic mean-field, theory. We start by generalizing the Doniach type phase diagram with substitution by considering the phases: ferromagnetic, antiferromagnetic, and paramagnetic Kondo. We also study the relevance of our phase diagrams by comparing the experimental data of various cerium-based Kondo alloys. Next, we will focus on the Kondo paramagnetic phase on a square lattice in order to study the signatures of lattice coherence breakdown with the dilution of magnetic impurities. To do this, we analyze the photoemission signals, the effective masses, the local potential scattering, and the charge order. We confirmed previous predictions of a Lifshitz-type transition between dilute and dense impurity systems. In addition, we detect a new critical concentration where the quasiparticle effective mass cancels out. The second part of this thesis deals with the dual character of 5f electrons: itinerant and localized at the same time. To study this duality, we use the method rotationally invariant slave-bosons on UPt3. By varying the anisotropies over the electronic bandwidths, we study the possibility of having orbital selective partially localized phases, and we construct a phase diagram. Finally, we analyze the different partially localized phases in terms of orbital-dependent quasiparticle mass and occupation, magnetization, and valency configurations.

[tel-03688895] Lattice coherence and local non-local duality in f -electron materials

ano.nymous@ccsd.cnrs.fr.invalid (Bishal Poudel) — Wed, 09 Nov 2022 03:27:55 +0000

n this thesis, we will study f -electron systems under two different aspects: the formation and the breakdown of lattice coherence, and the nature of f -electrons, which can be either localized, itinerant, or dual. In the first part, we study lattice coherence in 4f systems with the atomic substitution of magnetic atoms by non-magnetic atoms. We will deal with the ubstitutional disorder by using the dynamic mean-field, theory. We start by generalizing the Doniach type phase diagram with substitution by considering the phases: ferromagnetic, antiferromagnetic, and paramagnetic Kondo. We also study the relevance of our phase diagrams by comparing the experimental data of various cerium-based Kondo alloys. Next, we will focus on the Kondo paramagnetic phase on a square lattice in order to study the signatures of lattice coherence breakdown with the dilution of magnetic impurities. To do this, we analyze the photoemission signals, the effective masses, the local potential scattering, and the charge order. We confirmed previous predictions of a Lifshitz-type transition between dilute and dense impurity systems. In addition, we detect a new critical concentration for a Fermi liquid instability. The latter is highlighted by a vanishing effective mass. The second part of this thesis deals with the apparent dual character of 5f electrons in actinide-based heavy-fermion compounds, where itinerant and localized 5f -degrees of freedom seem to coexist. We adopt the rotationally invariant slave-boson method to study the influence of intra-atomic, i. e., Hund’s rule type correlations. Our results confirm the conjecture that intra-atomic correlations may enhance anisotropies in the effective 5f -5f hopping and thus eventually lead to orbital-selective partial localization. Finally, we analyze the different partially localized phases in terms of orbital-dependent quasiparticle mass and occupation, magnetization, and valency configurations.

[insu-03656916] Constraints on the structure and seasonal variations of Triton's atmosphere from the 5 October 2017 stellar occultation and previous observations

ano.nymous@ccsd.cnrs.fr.invalid (J. Marques Oliveira) — Tue, 06 Dec 2022 12:42:13 +0000

Context. A stellar occultation by Neptune's main satellite, Triton, was observed on 5 October 2017 from Europe, North Africa, and the USA. We derived 90 light curves from this event, 42 of which yielded a central flash detection. Aims: We aimed at constraining Triton's atmospheric structure and the seasonal variations of its atmospheric pressure since the Voyager 2 epoch (1989). We also derived the shape of the lower atmosphere from central flash analysis. Methods: We used Abel inversions and direct ray-tracing code to provide the density, pressure, and temperature profiles in the altitude range ~8 km to ~190 km, corresponding to pressure levels from 9 µbar down to a few nanobars. Results: (i) A pressure of 1.18 ± 0.03 µbar is found at a reference radius of 1400 km (47 km altitude). (ii) A new analysis of the Voyager 2 radio science occultation shows that this is consistent with an extrapolation of pressure down to the surface pressure obtained in 1989. (iii) A survey of occultations obtained between 1989 and 2017 suggests that an enhancement in surface pressure as reported during the 1990s might be real, but debatable, due to very few high S/N light curves and data accessible for reanalysis. The volatile transport model analysed supports a moderate increase in surface pressure, with a maximum value around 2005-2015 no higher than 23 µbar. The pressures observed in 1995-1997 and 2017 appear mutually inconsistent with the volatile transport model presented here. (iv) The central flash structure does not show evidence of an atmospheric distortion. We find an upper limit of 0.0011 for the apparent oblateness of the atmosphere near the 8 km altitude.

Light curves are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/659/A136

HAL : Dernières publications

[hal-03863641] Axisymmetric Shell Modelling of Viscoelastic Yeast Cells in the Finite Strain Range

[hal-03054291] Quantifying the rationality of rhythmic signals

[hal-03952671] Core–shell nanoheterodimers: laser-assisted deposition of single bimetallic Au@M (M = Au, Ag, Pd, Pt) nanodots on TiO2 nanoparticles

[hal-03694008] Nanoparticle Taylor dispersion near charged surfaces with an open boundary

[hal-03919921] Numerical simulation of universal morphogenesis of fluid interface deformations driven by radiation pressure

[hal-03892664] Mechanical response of a thick poroelastic gel in contactless colloidal-probe rheology

[hal-03889405] On the bridge hypothesis in the glass transition of freestanding polymer films

[hal-03887792] Specular reflection and transmission of electromagnetic waves by disordered metasurfaces

[hal-03906476] Kinetics and wavelength dependence of thermal and gain lens induced in Nd:YAG rod amplifier

[hal-03713580] Non-Gaussian diffusion near surfaces

[hal-03872584] Drifting/Diffusive Regime Transition of Deformable Particles in a Honeycomb Network

[hal-03871719] Spin‐Orbit Modal Optical Vortex Beam Shaping from Dielectric Metasurfaces

[hal-03863984] Inhibition of membrane repair protein annexin-A2 prevents tumor invasion and metastasis

[hal-03864020] Annexin-A5 and annexin-A6 silencing prevents metastasis of breast

[hal-03763969] Dynamical scaling as a signature of multiple phase competition in Yb 2 Ti 2 O 7

[hal-03854416] Mesoscopic Klein-Schwinger effect in graphene

[hal-03848448] Mechanical characterization of core-shell microcapsules

[hal-03843477] Surface and Bulk Relaxation of Vapour-Deposited Polystyrene Glasses

[hal-03871659] Observation of Polarization Singularities and Topological Textures in Sound Waves

[hal-03832770] Numerical simulations of confined Brownian motion

[hal-03810529] Exact solutions for viscous Marangoni spreading

[hal-03685227] Schwinger boson theory of the J1,J2=J3 kagome antiferromagnet

[hal-03863624] Experimental measurement of heat transport property: Why is heat transport modelling required for nanometrology?

[hal-03809735] Effective temperature and dissipation of a gas of active particles probed by the vibrations of a flexible membrane

[hal-03696161] Microscopic foundation of the $\mu$(I) rheology for dense granular flows on inclined planes.

[hal-03810977] Influence of Generated Defects by Ar Implantation on the Thermoelectric Properties of ScN

[hal-03863674] Why is heat transport modelling required for nanometrology?

[hal-03788404] Activity Induced Rigidity of Liquid Droplets

[tel-03813782] Dispersion dans les milieux hétérogènes : une étude des effets hydrodynamiques et de la diffusion médiée par la surface.

[hal-03781137] Rotation Control, Interlocking, and Self‐Positioning of Active Cogwheels

[hal-03776303] Everlasting impact of initial perturbations on first-passage times of non-Markovian random walks

[hal-03617124] Frustration on a centred pyrochlore lattice in metal-organic frameworks

[hal-03763970] Observing Magnetic Monopoles in Spin Ice using Electron Holography

[hal-03302160] Structural magnetic glassiness in spin ice Dy_2Ti_2O_7

[hal-03707419] Droplet impacts on cold surfaces

[hal-03871587] Optical cloaking of macroscopic objects by geometric-phase vortex processing

[hal-03719127] Lift at low Reynolds number

[tel-03772522] Charge-Transfer Chemical Reactions and Chiral Discrimination in Electromagnetic Fabry-Pérot Cavities

[hal-03633285] Giant Diffusion of Nanomechanical Rotors in a Tilted Washboard Potential

[hal-03376419] Structural characterization of the interfacial self-assembly of chitosan with oppositely charged surfactant

[hal-03863814] Two-layers cell-wall modelling for S. cerevisiae yeast

[hal-03685547] How stickiness can speed up diffusion in confined systems

[tel-03813680] Revisiting statistical physics tools for the complex time-frequency characterization of physiological signals

[hal-03653650] Profil d'un câble tracté

[hal-03686607] Design, elaboration and characterization of an immunosensor for the detection of a fungal toxin in foodstuffs analyses

[hal-03495457] Femtosecond OPO pumped by a high power ytterbium rod-type fiber laser mode locked at harmonic repetition rates

[hal-03764767] Design, Elaboration, and Characterization of an Immunosensor for the Detection of a Fungal Toxin in Foodstuff Analyses

[tel-03717655] Lattice coherence and local non-local duality in f-electron materials

[tel-03688895] Lattice coherence and local non-local duality in f -electron materials

[insu-03656916] Constraints on the structure and seasonal variations of Triton's atmosphere from the 5 October 2017 stellar occultation and previous observations

[hal-03952671] Core–shell nanoheterodimers: laser-assisted deposition of single bimetallic Au@M (M = Au, Ag, Pd, Pt) nanodots on TiO₂ nanoparticles