Jérémie Margueritat

• PhD, HDR CNRS researcher, main interest: Acoustic Vibration of Nano-object
• Researcher at Claude Bernard University Lyon 1

Brillouin Light Scattering (BLS) spectroscopy is a non-invasive, non-contact, label-free optical technique that can provide information on the mechanical properties of a material on the sub-micron scale. Over the last decade it has seen increased applications in the life sciences, driven by the observed significance of mechanical properties in biol...

Brillouin Light Scattering (BLS) spectroscopy is a non-invasive, non-contact, label-free optical technique that can provide information on the mechanical properties of a material on the sub-micron scale. Over the last decade it has seen increased applications in the life sciences, driven by the observed significance of mechanical properties in biol...

The ability of thin materials to shape-shift is a common occurrence that leads to dynamic pattern formation and function in natural and man-made structures. However, harnessing this concept to rationally design inorganic structures at the nanoscale has remained far from reach due to a lack of fundamental understanding of the essential physical comp...

In a recent article published in Viruses by Manna et al. [...]

The ability of thin materials to shape-shift is a common occurrence that leads to dynamic pattern formation and function in natural and man-made structures. However, harnessing this concept to design inorganic structures at the nanoscale rationally has remained far from reach due to a lack of fundamental understanding of the essential physical comp...

The vibrational dynamics in the sub-THz range of mesoporous silica nanoparticles (MSNs) having ordered cylindrical mesopores was investigated. MCM-41 and SBA-15 particles were synthesized, and their structure was determined using scanning electron microscopy (SEM), low-angle X-ray diffraction (XRD), N2 physisorption analyses, and Raman scattering....

En 1922, Léon Brillouin publie seul et en français, dans les comptes rendus de physique un article sur la diffusion de la lumière par des ondes acoustiques d’origine thermique. Il démontre que ces ondes acoustiques induisent un décalage en fréquence de la lumière diffusée. L'invention des lasers a rendu cette diffusion très efficace et permis de no...

Significance Plants need to constantly adapt to a changing environment. Adaptation includes responses to biotic and abiotic stress. Key elements determining the response to abiotic stress are the cell walls surrounding all plant cells and the phytohormone abscisic acid, which influence turgor pressure in plants. Turgor pressure in plant cells is mu...

Plant cells can be distinguished from animal cells by their cell walls and high turgor pressure. Although changes in turgor and stiffness of cell walls seem coordinated, we know little about the mechanism responsible for coordination. Evidence has accumulated that plants, like yeast, have a dedicated cell wall integrity maintenance mechanism. This...

The influence of ligands on the low frequency vibration of cadmium selenide colloidal nanoplatelets of different thicknesses is investigated using resonant low frequency Raman scattering. The strong vibration frequency shifts induced by ligand modifications as well as sharp spectral linewidths make low frequency Raman scattering a tool of choice to...

The coupling effects affecting the vibrations of two close nanostructures (e.g., two metal nanoplates or nanospheres separated by a thin dielectric layer) may considerably alter their vibrational eigenfrequencies, as demonstrated by several recent experimental studies. In this work, we present theoretical investigations of these coupling processes...

The influence of ligands on the low frequency vibration of different thicknesses cadmium selenide colloidal nanoplatelets is investigated using resonant low frequency Raman scattering. The strong vibration frequency shifts induced by ligand modifications as well as the sharp spectral linewidths make low frequency Raman scattering a tool of choice t...

The coupling effects affecting the vibrations of two close nanostructures (e.g., two metal nanoplates or nanospheres separated by a thin dielectric layer) may considerably alter their vibrational eigenfrequencies, as demonstrated by several recent experimental studies. In this work, we present theoretical investigations of these coupling processes...

Au nanoparticles (NPs) characterized by distinct surface chemistry (including dodecanethiol or oleylamine as capping agent), different sizes (~5 and ~10 nm) and crystallinities (polycrystalline or single crystalline), were chosen as seeds to demonstrate the versatility and robustness of our two-step core-shell Au@Ag NP synthesis process. The centra...

Les spectroscopies vibrationnelles sont des techniques de caractérisation optique très répandues et utilisées dans de nombreux domaines scientifiques et industriels. Elles bénéficient depuis plusieurs années d’un grand essor, de par les nombreuses innovations technologiques qui les rendent de plus en plus performantes et utilisables sur des nombreu...

Measuring the complex mechanical properties of biological objects has become a necessity to answer key questions in mechanobiology and to propose innovative clinical and therapeutic strategies. In this context, Brillouin light scattering (BLS) has recently come into vogue, offering quantitative imaging of the mechanical properties without labels an...

Light scattering (Raman, Rayleigh and Mandelshtam-Brillouin) and absorption of commercial color glasses (cut-off optical filters containing nanocrystals of ternary compounds CdSxSe1–x) were studied. It was found for the first time that the contribution of nanocrystals to the Rayleigh scattering is unprecedentedly low for some of these glasses. This...

Lamb modes describe the vibrations of an object as a whole from the stellar scale to the nanometer one. Lamb description has been built from the linear elasticity theory and considers a homogeneous elastic sphere. Our work tries to determine the minimum scale where this description remains valid by studying the vibration of quantum sized gold clust...

Highly loaded lubricated contacts may present a friction plateau on which the friction force becomes independent from the sliding velocity. Although this phenomenon has been known for a long time, its physical origin remains poorly known. The present paper aims at giving further insight on the physical mechanisms triggering the friction plateau. Th...

We report the synthesis of long narrow gold nanocrystals and the study of their vibrational dynamics using inelastic light scattering measurements. Rich experimental spectra are obtained for monodomain gold nanorods and pentagonal twinned bipyramids. Their assignment involves diameter-dependent non-totally symmetric vibrations which are modeled in...

The structure of teeth can be altered by diet, age or diseases such as caries and sclerosis. It is very important to characterize their mechanical properties to predict and understand tooth decay, design restorative dental procedures, and investigate their tribological behavior. However, existing imaging techniques are not well suited to investigat...

The structure of tumors can be recapitulated as an elastic frame formed by the connected cytoskeletons of the cells invaded by interstitial and intracellular fluids. The low-frequency mechanics of this poroelastic system, dictated by the elastic skeleton only, control tumor growth, penetration of therapeutic agents, and invasiveness. The high-frequ...

Our study proposes a new way to observe and explain the presence of extended plasmonic modes in disordered semi-continuous metal films before the percolation threshold. Attenuated total reflection spectroscopy allows us to follow the transition of plasmon modes from localized to delocalized resonances, but also reveals unobserved collective plasmon...

The acoustic vibrations of single monomers and dimers of gold nanoparticles were investigated by measuring for the first time their ultra-low frequency micro-Raman scattering. This experiment provides access not only to the frequency of the detected vibrational modes, but also to their damping rate, which is obscured by inhomogeneous effects in mea...

Studies of the mechanical contact between nanometer-scale particles provide fundamental insights into the mechanical properties of materials and the validity of contact laws at the nanoscale which are still under debate for contact surfaces approaching atomic dimensions. Using in-situ Brillouin light scattering under high pressure, we show that eff...

Energy dissipation in amorphous coatings severely affects high-precision optical and quantum transducers. In order to isolate the source of coating loss, we performed an extensive study of Raman scattering and mechanical loss of a thermally-treated sputtered silica coating. Our results show that loss is correlated with the population of three-membe...

Energy dissipation in amorphous coatings severely affects high-precision optical and quantum transducers. In order to isolate the source of coating loss, we performed an extensive study of Raman scattering and mechanical loss of a thermally-treated sputtered silica coating. Our results show that loss is correlated with the population of three-membe...

The low frequency Raman scattering from gold nanoparticle bimodal assemblies with controlled size distributions has been studied. Special care has been paid to determining the size dependence of the Raman intensity corresponding to the quadrupolar Lamb mode. Existing models based on a microscopic description of the scattering mechanism in small par...

Resonant acoustic modes from ultrathin CdS colloidal nanoplatelets (NPLs) are probed under high pressure using low frequency Raman spectroscopy. In particular we focus on the characterization of the recently evidenced mass load effect that is responsible for a significant downshift of the NPL breathing frequency due to the inert mass of organic lig...

Resonant acoustic modes from ultrathin CdS colloidal nanoplatelets (NPLs) are probed under high pressure using low frequency Raman spectroscopy. In particular we focus on the characterization of the recently evidenced mass load effect that is responsible for a significant downshift of the NPLs breathing frequency due to the inert mass of the organi...

The onset of the sintering of 5 nm ZrO2 and TiO2 nanoparticles is investigated by various methods including inelastic light scattering. A special attention is paid to low-frequency Raman spectra where scattering from confined acoustic vibrations and quasielastic scattering manifest. Significant changes are observed between samples sintered at diffe...

Resonant acoustic modes of ultrathin CdS and CdSe colloidal nanoplatelets (NPLs) with varying thicknesses were probed using low frequency Raman scattering. The spectra are dominated by an intense band ascribed to the thickness breathing mode of the 2D nanostructures. The measured Raman frequencies show strong deviations with respect to the values e...

Acoustic vibrations of assemblies of gold nanoparticles were investigated using ultra low frequency micro-Raman scattering and finite element simulations. When exciting the assemblies resonantly with the surface plasmon resonance of electromagnetically coupled nanoparticles Raman spectra present an ultra-low frequency band whose frequency lies belo...

Modelling the mechanical response of silica glass is still challenging, due to the lack of knowledge concerning the elastic properties of intermediate states of densification. An extensive Brillouin Light Scattering study on permanently densified silica glasses after cold compression in diamond anvil cell has been carried out, in order to deduce th...

In this contribution, we report the identification of the principal reference Raman spectra of a single cystein molecule. To that purpose, we design an active Surface Enhanced Raman Spectroscopy (SERS) template based on surfactant-less Chebyshev nanoparticles operating in a microfluidic platform. A principal component analysis is obtained from fluc...

The effect of an applied high pressure on the optical and acoustic vibrations of small anatase TiO2 nanoparticles is studied using Raman scattering. All the Raman peaks show a significant variation of their frequency with pressure, except for the low-frequency peak which is due to acoustic vibrations confined in the nanoparticles. These variations...

The in situ elastic and plastic behaviors of sodium aluminosilicate glasses with different degrees of depolymerization were analyzed using Brillouin spectroscopy. The observed elastic anomaly progressively vanished with depolymerization. The densification process appears to be different from that observed in pure silica glass. In the plastic regime...

We introduce a novel experimental and analytical method for discerning rare surface-enhanced Raman scattering (SERS) events observable at the nanoscale. We show that the kinetics of the Raman activity recorded on an isolated nanostructure is punctuated by intense and rare events of large amplitude and spectral variations. The fluctuations of thousa...

Raman scattering experiments have been carried out to study persistent densification in SiO(2) glass following hydrostatic compression at room temperature. A new relationship linking selective Raman parameters to the degree of densification in the glass has been developed here. This approach will allow quantification of the residual densification i...

The elastic and plastic behaviors of silica glasses densified at various maximum pressure reached (12 GPa, 15 GPa, 19 GPa, and 22 GPa), were analyzed using in situ Raman and Brillouin spectroscopies. The elastic anomaly was observed to progressively vanish up to a maximum pressure reached of 12 GPa, beyond which it is completely suppressed. Above t...

Several-nanometer-size mechanical oscillators, or nanoresonators, may complement electronic and optical technologies in future terahertz devices, but they can be useful only if they can be made to have relatively light damping, that is, a quality factor as high as possible. Completely mechanically isolated nanoparticles a few nanometers in size wou...

In the present work, the combination of chemical immobilization with electron beam lithography enables the production of sensitive and reproducible SERS-active areas composed of stochastic arrangements of gold nanoparticles. The number of nanoparticles was varied from 2 to 500. Thereby a systematic analysis of these SERS-active areas allows us to s...

Klebsormidium flaccidum algalcells exhibiting the ability to form gold nanoparticles intra-cellularly in suspension were encapsulated within silica gels. Optical and electronic microscopy indicate that entrapped cells maintain their ability to reduce gold salts. A difference in the kinetics of gold colloid formation within silica in the absence or...

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Scitation is the online home of leading journals and conference proceedings from AIP Publishing and AIP Member Societies

This work shows the production of self-assembled elongated nano-objects embedded in an oxide host oriented perpendicular to the substrate and their acousto-plasmonic dynamics. Electromagnetic #x201C;hot spots #x201D; are created that activate anomalous Raman vibrational modes.

Plasmonic structures are commonly used to both confine and enhance surface electromagnetic fields. In the past ten years, their peculiar optical properties have given rise to many promising applications ranging from high density data storage to surface optical trapping. In this context, we investigated both far-field and near-field optical response...

We investigate the acousto-plasmonic dynamics of metallic nano-objects by means of resonant Raman scattering and time-resolved femtosecond transient absorption. We observe an unexpectedly strong acoustic vibration band in the Raman scattering of silver nanocolumns, usually not found in isolated nano-objects. The frequency and the polarization of th...

Optical antennas are elementary units used to direct optical radiation to the nanoscale. Here we demonstrate an active control over individual antenna performances by an external electrical trigger. We find that by an in-plane command of an anisotropic load medium, the electromagnetic interaction between individual elements constituting an optical...

A powerful capability of metallic nano-objects is to serve as enhancers of the Raman signal in a large variety of spectroscopies (SERS, SEIRA). We focus in this work on the role of plasmons on the excitation of acoustic vibrations of metallic nano-objects. The coupling between acoustic vibrations and surface plasmons still presents several theoreti...

We report the preparation of a new type of nanocomposite containing cobalt and silver nanoparticles organized in parallel layers with a well controlled separation. This arrangement allows the observation of an enhanced low-frequency Raman signal at the vibration frequency of cobalt nanoparticles excited through the surface plasmons of silver nanopa...

Using ultrafast spectroscopy, we investigated electron-lattice coupling and acoustic vibrations in self-assembled silver nanocolumns embedded in an amorphous Al2O3 matrix. The measured electron-lattice energy exchange time is smaller in the nanocolumns than in bulk silver, with a value very close to that of isolated nanospheres with comparable surf...

Nous avons développé de nouveaux concepts de fabrication de matériaux nanostructurés en couche mince basés sur le dépôt par ablation laser alterné d'un métal (Ag) et d'un diélectrique (Al2O3). Cette technique permet d'atteindre un contrôle optimal sur les paramètres morphologiques des nanostructures qui déterminent la réponse optique des couches mi...

The coupling between surface plasmon polaritons and confined acoustic vibrations in embedded silver nanoparticles is studied both theoretically and experimentally. The inelastic light scattering spectra simulated assuming deformation potential and surface orientation mechanisms are quantitatively compared to Raman measurements. The effects of size...

Optical and vibrational properties of silver nanolentils, nanospheres, and nanocolumns are studied experimentally using optical transmission spectroscopy and low-frequency Raman scattering. The split of the surface plasmon–polariton resonance into transverse and longitudinal components due to the squeezing or to the elongation of the nanospheres is...

We compare the magnetic properties of pure and oxidized Co nanoparticles embedded in an amorphous Al 2 O 3 matrix. Nanoparticles with diameters of 2 or 3 nm were prepared by alternate pulsed laser deposition in high vacuum conditions, and some of them were exposed to O 2 after production and before being embedded. The nanoparticles are organized in...

The authors present a study of the optical and magneto-optical properties of Co nanoparticles embedded in two amorphous dielectric matrices with different refractive indices such as ZrO2 and Al2O3. The nanostructured films were prepared by pulsed laser deposition, and the morphology and structure were studied by different characterization technique...

Optical and vibrational properties of novel self-assembled silver nanocolumns are studied experimentally and theoretically. The split of the surface plasmon resonance into transverse and longitudinal modes verifies the one-dimensional character of the nanocolumns. In this work, we have identified the acoustic vibration modes of the nanocolumns usin...

Self-aligned silver nanocolumns embedded in amorphous Al2O3 matrix are produced by alternate pulsed laser deposition at room temperature in a single step process. The morphology and the spatial distribution have been investigated by standard, high resolution, and scanning transmission electron microscopy. Polycrystalline nanocolumns having diameter...

We present a study of the magnetic properties of oxidized Co nanoparticles with an average grain size of 3 nm , embedded in an amorphous Al ₂ O ₃ matrix. These nanoparticles can be considered as imperfect Co-core CoO-shell systems. Magnetization measurements after magnetic field cooling show a vertical shift of the hysteresis...

Nous avons développé de nouveaux concepts de fabrication de matériaux nanostructurés en couche mince basés sur le dépôt par ablation laser alterné d'un métal (Ag) et d'un diélectrique (Al$_{2}$O$_{3}$). Cette technique permet d'atteindre un contrôle optimal sur les paramètres morphologiques des nanostructures qui déterminent la réponse optique des...

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física de Materiales. Fecha de lectura: 21-04-08 Bibliografía