Дисертації з теми "Spectroscopies exaltées de surface"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 дисертацій для дослідження на тему "Spectroscopies exaltées de surface".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
Edely, Mathieu. "Etudes de surfaces métalliques nanolithographiées : application à la diffusion Raman exaltée de surface." Thesis, Le Mans, 2016. http://www.theses.fr/2016LEMA1020.
Since the first observation of Surface Enhanced Raman Scattering (SERS) in 1974 a variety of methods have been developed to physically control the arrangement of metallic nanostructures onto a surface in order to enhance Raman signals. The magnitude of the SERS enhancement factor is mainly driven by the enhanced local electromagnetic field in nanostructured metal surfaces. Gaps between adjacent nanoparticles give rise to strong enhancement effects, often referred as ‘hot spots’. One way to produce highly efficient SERS substrates is to develop a reproducible system of interacting metal nanostructures capable of high field enhancement.We patented a force-assisted Atomic Force Microscopy lithographic method allowing the fabrication of a metallic substrate. It will be shown that this method also provides a relatively simple approach to realize reproducible patterns with controlled geometry that can be used to study the influence of specific pattern geometry on SERS phenomenon.In order to investigate the relationship between optical properties and pattern geometries, localized surface plasmon resonance (LSPR) and local electric field enhancement are simulated.Whereas electric field enhancement regions (hot spot) have been observed on the top of the nanostructures with PhotoEmission Electron Microscopy (PEEM), SERS effect has been demonstrated by performing Raman measurements using several probe molecules. Correlations between PEEM measurements, Raman exaltation and local field calculations are presented in relation with the geometrical parameters of the nanostructured patterns
Lopes, Manuel. "Etude de nanoantennes optiques : application aux diffusions Raman exaltées de surface et par pointe." Phd thesis, Université de Technologie de Troyes, 2008. http://tel.archives-ouvertes.fr/tel-00357221.
Ensuite, j'ai monté une expérience de Raman en champ proche (ou TERS) et développé une technique reproductible de fabrication de pointes en or. Puis, j'ai effectué une étude quantitative des propriétés de dépolarisation des pointes métalliques utilisées en a-SNOM et en TERS. Nos résultats montrent des facteurs de dépolarisation entre 5 et 30% qui varient en fonction de la polarisation de la lumière incidente et de la forme de la pointe. Les conséquences importantes de ce phénomène de dépolarisation ont été mises en évidence dans des expériences TERS sur du Silicium cristallin; On montre que la dépolarisation doit être prise en compte pour une estimation correcte de l'exaltation induite par la pointe.
Rastogi, Rishabh. "Engineered Electromagnetic Hot-spots for Highly Sensitive (Bio)molecular Detection by Plasmonic Specytroscopies." Thesis, Troyes, 2020. http://www.theses.fr/2020TROY0018.
Nanoplasmonic sensing relies on enhanced electromagnetic fields at the vicinity of nanostructured metal surface to detect molecules at ultra-low concentrations. The EM enhancements are strongly pronounced at junctions between adjacent nanostructures resulting in gap hot-spots. EM enhancements at these hot-spots increase non-linearly as a function of gap distances down to sub-10 regime. Analyte present at these gaps can leverage these EM enhancements, resulting in ultra-high sensitivity in detection. However, such confining gaps affect the ability of large analytes such as biomolecules to enter and thereby leverage EM fields within the gaps. This presents spatial needs to enhance EM fields at odds with those for accommodating biomolecular interactions. This thesis demonstrates the rational design of array configurations that allows the EM hotspots to be better leveraged by the reporter of biomolecular binding event. The thesis uses molecular self-assembly based approach to fabricate reproducible plasmonic nanoarrays on full wafers. Multiple parameters are considered including the dimension, shape, and density of hotspots, surface functionalization, and the choice of substrates, to demonstrate quantitative detection of molecules down to picomolar concentrations
Haidar, Israa. "Nouvelles plateformes plasmoniques pour la spectroscopie Raman exaltée de surface." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCC307.
The design of novel plasmonic platforms for Surface Enhanced Raman Spectroscopy (SERS) constitutes a very active field of research in nanosciences. Such platforms can be used for the detection and identification of various analytes at very low concentration, through a huge amplification of the Raman signal, resulting from the excitation of localized surface plasmon resonances. The main objective of my phd is to develop and to characterize new SERS substrates obtained by chemical assembly (surface functionalization) of nanoparticles with controlled hot spots. Design of such substrates contributes to a better understanding of the mechanisms of electromagnetic enhancement considered at the origin of the SERS effect
Delhaye, Caroline. "Spectroscopie Raman et microfluidique : application à la diffusion Raman exaltée de surface." Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13927/document.
This thesis focuses on the development of a microfluidic platform coupled with confocal Raman microscopy, used in excitation conditions of Raman scattering (Surface enhanced Raman scattering, SERS) in order to gain in the detection sensitivity of molecular species flowing in channels of micrometer dimensions. This work aims to demonstrate the feasibility of coupling Raman microscopy / microfluidics for the in situ and local characterization of species and reactions taking place in the fluid flowing in microchannels. We used a T-shaped microchannel, made by soft lithography, in which gold or silver nanoparticles injected at constant speed, in one of the two branches of the channel and a solution of pyridine or pefloxacin in the other one. The laminar flow and the stationarity of the process allowed us to map the mixing zone and highlight the enhancement of the Raman signal of pyridine and pefloxacin, due to the metallic nanoparticles, in the interdiffusion zone. The recording of the both absorption band of the silver nanoparticles (plasmon band) and the Raman signal of pefloxacin, flowing in microchannel, allowed us to establish a link between the shape of the metallic nanostructure, and more precisely the silver nanoparticle aggregation state, and the enhancement of the Raman signal of pefloxacin observed. We then changed the channel geometry to introduce an electrolyte solution (NaCl and NaNO3) and locally modify the surface charge of the colloids. We have put in evidence that the change of the silver nanoparticle aggregation state, induced by the controlled addition of electrolyte solutions, could amplify the SERS signal of pefloxacin and thus optimizing the detection in microfluidics. At last, we established second a approach that consists in the metallic structuring of microchannel walls. This has shown that the surface chemical functionalization through organosilanes (APTES) allowed the pasting of the channel with silver nanoparticles, thus amplifying the Raman signal of the species flowing within the same microchannel
Makiabadi, Tahereh. "Etude de surfaces nanostructurées : applications à la spectroscopie Raman exaltée de surface et à la résonance de plasmons localisés." Phd thesis, Université de Nantes, 2010. http://tel.archives-ouvertes.fr/tel-00467582.
Makiabadi, Tahereh. "Étude de surfaces nanostructurées : applications à la spectroscopie Raman exaltée de surface et à la résonance de plasmons localisés." Nantes, 2010. http://archive.bu.univ-nantes.fr/pollux/show.action?id=eb8aaf03-cd71-46c6-a427-2c4cf47a3a49.
The objectives of this work are the realization, characterization and optimization of nanostructured surfaces, e. G. Substrates for the surface-enhanced Raman spectroscopy and the surface plasmon resonance. Several main contributions were performed. The first one is based on the grafting of silver and gold nanoparticles on functionalized supports. Our bottomup approach enabled us to highlight the optimal conditions to obtain a mono-layer of nanoparticles, with homogeneous distribution and an important density. The curves of extinction and factors of exaltation were quantified and modeled. Also, the manufacturing time was optimized. The second contribution, which is based on a top-down approach, consists of making nanostructures by electro erosion of a thin film of silver or gold, carried out by physical deposit in vapor phase. This procedure, which relies on the optimization of oxidation-reduction cycle (ORC), was employed to realize rough films and metal nanostructures. The presence of nanostructures and the nano cavities on the substrates were confirmed by scanning electron microscopy (SEM) atomic force microscopy (AFM). The limit of detection by Raman spectrometry was evaluated at 1nM. The optimal conditions obtained from the curves of extinction and Raman scattering made it possible to converge towards a reliable and reproducible manufacturing protocol. The third contribution is the deposit of nanoparticles on optical fibers in order to evaluate the sensitivity of the localized surface plasmon resonance (LSPR)
Julien, Carine. "Fluorescence et Diffusion Raman exaltée de surface (SERS) de molécules individuelles." Phd thesis, Université Paris Sud - Paris XI, 2004. http://tel.archives-ouvertes.fr/tel-00011564.
Par microscopie grand champ de fluorescence, l'émission de molécules uniques de pérylène orange insérées dans un film solgel mince, par enregistrement de films d'une large zone de l'échantillon sur laquelle plus d'une centaine d'émetteurs individuels sont détectés, fournit des informations sur cette espèce et la matrice sondée. Pour exploiter les films, un outil logiciel a été développé. Les processus de photoblanchiment, la mobilité moléculaire, la nucléation des molécules excitées sont mis en évidence et discutés. On note une grande richesse des dynamiques temporelles d'émission, mais aussi des spectres qui reflètent notamment la reconformation proposée du pérylène orange excité. Il s'ensuit l'existence de nombreux nanoenvironnements différents dans la matrice poreuse.
Par microscopie confocale à balayage, le signal de diffusion Raman exaltée de surface de molécules uniques organique adsorbées sur des agrégats d'argent de morphologie complexe est exploité. Certains objets présentent une exaltation géante, estimée être de plus de 14 ordres de grandeur, ce qui permet l'enregistrement de spectres résolus en seulement une seconde. L'analyse chimique offerte permet de distinguer différentes espèces, et la présence nécessaire sur ces points chauds d'Ag+ est démontrée. Une caractérisation corrélée par microscopie électronique des agrégats actifs repérés met aussi en avant l'existence d'une morphologie privilégiée, avec de nombreuses protubérances de dimension nanométrique et interstices.
Yazidi, Senda. "Structure et propriétés optiques de nanoparticules couplées : application à la spectroscopie Raman exaltée de surface." Thesis, Poitiers, 2018. http://www.theses.fr/2018POIT2279/document.
The aim of this work is to use nanostructured alumina surfaces to guide the growth and to optimize the organization of metallic particles (Ag, Au and AgxAu1-x), and to test those systems as reusable SERS-active substrates. We used spectrophotometry to characterize the resulting optical properties, spectroscopic ellipsometry for the determination of the optical index and transmission electron microscopy for the structural characterizations. Surfaced-enhanced Raman spectroscopy (SERS) was used for the detection of adsorbed bipyridine molecules on the sample surface, in collaboration with the Institut des Matériaux Jean Rouxel at Nantes. We first study systems consisting of monometallic and bimetallic nanoparticles in order to understand the growth modes of such particle assemblies. A particular attention is paid to the influence of the sequential deposition of Au and Ag on the structural and optical properties. We show that different arrangements of bimetallic nanoparticles are obtained according to the deposition sequence used and that an alloy is obtained after ex situ annealing under vacuum. The near-field and far-field optical properties of AgxAu1-x nanoparticle alloys embedded in an alumina matrix are compared numerically by the finite difference time domain method, with those of pure metal nanoparticles. Our results indicate that pure metal nanoparticles exhibit a greater field enhancement than alloy nanoparticles. Finally, SERS experiments conducted with a dichroic system made of coupled Ag nanoparticles show that an intense SERS signal can be obtained with coated nanoparticles
Grand, Johan. "Plasmons de surface de nanoparticules : spectroscopie d'extinction en champs proche et lointain, diffusion Raman exaltée." Troyes, 2004. http://www.theses.fr/2004TROY0014.
The intrinsic weakness of the Raman process makes its application in a near field optical experiment rather difficult. Thus, as a first step towards near field Raman spectroscopy, we studied Surface-Enhanced Raman Scattering (SERS), a technique that enables the detection of very low concentration of molecules adsorbed on rough metallic surfaces. For the purpose of the near field experiments, these SERS-active samples have to be reproducible and yield good enhancement factors. By designing metallic nanoparticle grating through electron beam lithography, we manage to vary the shape, size and arrangement of the particles, hence enabling a fine tuning of the Localized Surface Plasmon Resonance (LSPR) over the whole visible spectrum. We then investigate the relationship between the spectral position of the LSPR and the SERS intensity. The enhancement factor turned out to depend not only on the spectral position of the LSPR, but also on the shape of the metallic nanoparticles on which the surface plasmon is localized. In the same time, we build up an Apertureless Scanning Near Field Optical Microscope (ASNPM) set-up. The microscope is based on an atomic force microscope and a confocal detection coupled to a spectrometer. The near field/far field discrimination is achieved through the use of a lock-in detection of a photon counting device. Using this set-up along with a white light continuum, generated by coupling a Photonic Crystal Fiber to a Ti:Sa laser, made it possible to investigate the near field optical response of metallic nanoparticle gratings at different excitation wavelengths. A photon counting scheme was then used to directly record near field “extinction” spectra
Bomers, Mario. "Fonctionnalisation de surface de résonateurs plasmoniques à base de semi-conducteur III-V pour la spectroscopie vibrationnelle exaltée." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS013/document.
This thesis deals with the surface functionalization of nanostructured plasmonic III-V semiconductors for surface-enhanced vibrational spectroscopy relevant to identify minute amounts of analyte molecules.The first chapter outlines the theoretical foundations of surface-enhanced vibrational spectroscopy based on plasmonics. Comparing the plasmonic properties of the degenerate semiconductor InAs(Sb):Si and of metals, here gold and gallium, it is found that the degenerate semiconductor is especially suited for surface-enhanced infrared (SEIRA) spectroscopy and that gallium with its plasmonic potential in the UV-VIS range is apt for surface-enhanced Raman spectroscopy (SERS). Both alternative plasmonic materials theoretically outperform gold in their respective spectral ranges. Nevertheless, gold and its chemical inertness remain interesting for enabling plasmonic enhanced vibrational spectroscopy in different chemical environments. The influence of aqueous environments on the material properties of III-V semiconductors is addressed in the second and in the third chapter. It is found that InAs(Sb):Si is chemical stable in water, but GaSb is not. A GaSb/InAsSb:Si compound layer structure was used to demonstrate that the depletion of antimony and the incorporation of oxygen at the GaSb-water interface transform 50 nm of crystalline GaSb to a gallium oxide in less than 14 hours. The gallium oxide has a mid-IR refractive index in the order of n=1.6 and thus less than half of the value of the mid-IR refractive index of GaSb. This change in refractive index upon oxidation can be exploited to blue-shift the localized plasmonic resonance of InAsSb:Si gratings on GaSb-substrates in the range from 5 µm to 20 µm by pedestal formation.In Chapter 4, the controlled chemical bonding of organic molecules to the approximately 3 nm thin native oxide layer of III-V semiconductor surfaces by phosphonic acid chemistry is presented. This paves the way for plasmonic enhanced all-semiconductor mid-IR biophotonic applications. In chapter 5, two different, but equally successful strategies to combine III-V based plasmonic resonators with microfluidic circuits are described. These results demonstrate that lab-on-the-chip applications based on III-V semiconductors are possible. Finally, the possibility to integrate plasmonic Gallium nanoparticles onto the III-V material platform for a potential combination of SEIRA and SERS applications is presented in chapter 6
Verger, Frédéric. "Spectroscopie infrarouge exaltée de surface pour la détection de composés organiques dissous dans le milieu marin." Phd thesis, Université Rennes 1, 2012. http://tel.archives-ouvertes.fr/tel-00732964.
Chapus, Lionel. "Organisation de nanoparticules de métaux nobles : application à la spectroscopie Raman exaltée de surface et à l'électrochimie." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066258/document.
Metallic nanoparticles (NPs) have been subjected to a growing interest these last years in various domains such as healthcare, environment or electronics. In this thesis, we were particularly interested in the application of NPs mono or bimetallic made of noble metals in plasmonic domain. In this way, we synthesized by organometallic route, monometallic NPs of gold, silver and copper with a diameter ranging from 5 to 11 nm and characterized by a narrow polydispersity. After deposition on a solid substrate, they organized themselves spontaneously in 3D forming individual supercrystals. We studied the optical properties of these supercrystals, by measuring their absorbance spectra in function of their thicknesses and the nature of the NPs. Then, we showed that these supercrystals can be used as SERS substrates. The mean diameter of the NPs is way smaller than the ones reported in the literature. These substrates display a uniform and reproductible signal from a supercrystal to another. The Raman spectra of coating agent (alkanethiols or alkylamines) have been collected and enhancement factor ranging from 103 to 104 have been calculated. After verification by electroreflectance of NPs stability over a wide potential range, we coupled SERS with electrochemistry by using a monolayer of organized gold NPs as an electrode. Coverage rates for two different molecules adsorbed on the NPs have been calculated. Moreover, we could follow and confirm the species formation during the oxydoreduction reactions of the adsorbed molecules by SERS. Finally, we synthesized core-shell NPs Au@Ag, Ag@Au and alloy NPs Cu-Au by using gold, silver and copper NPs as seeds. Their structures and chemical compositions have been studied. Their optical spectra have been measured by UV-Visible spectroscopy and simulated by DDA (Discrete Dipole Approximation). They confirmed the core-shell and alloy structures. By low frequency Raman spectroscopy, for the Au@Ag NPs, we showed a coupling between the core and the shell in accordance with the core-shell model developed in the literature. For the Cu-Au NPs, low-frequency Raman signal is in agreement with the formation of an alloy
Le, Nader Victor. "Approche expérimentale et théorique de la diffusion Raman exaltée : résonance des plasmons de surface et effet de pointe." Phd thesis, Université de Nantes, 2010. http://tel.archives-ouvertes.fr/tel-00559365.
PROCHAZKA, MAREK. "Etude d'interactions de porphyrines avec les acides nucleiques par spectroscopie diffusion raman exaltee de surface." Paris 6, 1997. http://www.theses.fr/1997PA066515.
Grimault, Anne-Sophie. "Modélisation du champ proche de structures résonantes 3D : application à la diffusion Raman exaltée de surface." Troyes, 2006. http://www.theses.fr/2006TROY0006.
We studied the position of the localized surface plasmon resonance and the surface enhanced Raman scattering of periodic arrays of metallic nanostructures with different size, form and environment. To calculate localized surface plasmon resonance and the Raman gain, we developed a numerical code based on the finite difference time domain method using the Drude-Lorentz dispersion model. Our results highlighted a strong influence of the geometry and environment of the nanoparticles on their resonance plasmon and their Raman signal. We observed dipolar and multipolar plasmon mode resonances as well as a shift between the position of the Plasmon resonance and the position of the maximum of the intensity of the Raman signal, whatever the size and the form of the nanoparticles. This numerical tool can thus make it possible to optimize manufacture of samples, by giving the parameters of size, form and environment necessary to achieve the most intense Raman signals
Gehan, Hélène. "Nano-structuration de substrats à points chaud contrôlés : application à la diffusion Raman exaltée de surface." Paris 7, 2010. http://www.theses.fr/2010PA077196.
Since the last decade, the development of coupled nanoparticles (NPs) assemblies has been particularly studied for applications in surface enhanced spectroscopy. In this field, the surface enhanced Raman scattering (SERS is considered as an extremely sensitive tool, allowing the detection of very few amounts of various molecules type (drugs, explosives, biological molecules). It requires very huge electromagnetic field enhancements occurring within the gap between coupled NPs, called hot-spot. However, one of the major difficulties is the non-reproducibility of these hot spots, occurring by generally random NPs aggregates. In this work, we propose to design and to characterize by SERS structured assemblies of coupled gold nanostructures. Two ways are explored: (i) the development of substrates in which coupled gold NPs are self-assembled in an patterned way. This strategy shows that a small amount of coupled NPs is favourable to the detection of few molecules. On the other hand, the case of a great amount of coupled NPs is rather favorable to common analytical studies. Moreover, this method is adaptable to various form of NPs. (ii) The second strategy consist in a plasmonic device made of gold NPs separated from a gold film through a thermoresponsive polymer layer. Studies using electrochemistry and SERS as the function of the temperature show an interaction between the gold film and the NPs. This interaction is dependent on the distance between these two entities which is controlled by conformational changes of the polymer layer in response to temperature variations. A new setup which can make an image of the near field enhanced areas. The main idea is about the adsorbate molecule which is sensible to the near field, although its enhanced Raman scattering detection is done in far field. We can say that the molecule frustrate the near field in order to give an image of this local field
Touzalin, Thomas. "Tip-enhanced Raman spectroscopy on electrochemical systems." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS364.
The in situ investigation of electrochemical interfaces structures at the nanoscale is a key element in the understanding of charge and electron transfer mechanisms e.g. in the fields of energy storage or electrocatalysis. This thesis introduces the implementation of tip-enhanced Raman spectroscopy (TERS) in liquid and in electrochemical conditions enabling the nanoscale analysis of electrified solid/liquid interfaces through the strong and local electric field enhancement at gold or silver scanning tunneling microscopy (STM) probes. The ability of TERS to image inhomogeneities in the coverage density of a self-assembled monolayer (SAM) through a layer of organic solvent on gold was demonstrated. A TERS-inspired analytical tool was also developed, based on a TERS tip used simultaneously as a single-hot spot surface-enhanced Raman spectroscopy (SERS) platform and as a microelectrode (EC tip SERS). The reduction of an electroactive SAM could then be monitored by electrochemical and in situ SERS measurements. In situ electrochemical STM-TERS was also evidenced through the imaging of local variations of the electric field enhancement on peculiar sites of a gold electrode with a lateral resolution lower than 8 nm. Finally TERS also demonstrated to be efficient in investigating the structure of organic layers grafted either by electrochemical reduction or spontaneously. This work is therefore a major advance for the analysis of functionalized surfaces
Thierry, Dominique. "Application de la spectroscopie raman exaltee de surface a l'etude in-situ d'inhibiteurs de corrosion du cuivre." Paris 6, 1988. http://www.theses.fr/1988PA066564.
Barho, Franziska Barbara. "Highly doped semiconductor plasmonic resonators for surface enhanced infrared absorption." Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTS075/document.
The detection and identification of biological and chemical substances can be performed with biosensors. Biosensors are required to be simple and rapid to use, small, and sensitive in order to detect minute amounts of analyte molecules. Plasmonic devices have proven their utility as biosensing transducers. Surface plasmon-polaritons (SPP), collective oscillations of the electron cloud in metallic media coupled to an electromagnetic wave, are sensitive to the refractive index of their environment, providing thus an efficient way to probe the presence of molecules by the refractive index modification. This technique is called surface plasmon resonance (SPR) sensing. Moreover, SPP confine the incident electric field to sub-wavelength dimensions and enhance the field strength. Molecules located in these so-called field hotspots interact more efficiently with incident light due to a coupling mechanism mediated by the SPP, so that their infrared (IR) absorption cross section is increased. While IR spectroscopy is a standard tool for molecular identification, it does not provide sufficient sensitivity for the detection of smallest quantities. Exploiting the surface enhanced IR absorption (SEIRA) due to the plasmonic enhancement enables the detection of small amounts of analyte.While surface plasmons were mainly discovered using noble metals such as gold and silver, nowadays other material systems are also considered which display complementary or improved properties compared to the standard materials in plasmonics, especially to enlarge the spectral range where plasmonic effects can be observed and exploited. Material science enables to tailor the dielectric function of a material and consequently to control the plasmonic properties. Highly doped III-V semiconductors constitute an alternative to gold and silver for mid-IR plasmonics, due to their dielectric function which resembles the one of the noble metals, but shifted to the mid-IR spectral range. Indeed, InAsSb in the IR is even less lossy than gold in the visible. SEIRA using plasmonic resonances spectrally tuned to molecular absorption lines, or resonant SEIRA, requires nanoantenna substrates displaying their resonances in the IR. Highly doped InAsSb grown lattice matched on GaSb substrates is an interesting material system for this task. InAsSb is plasmonic for wavelengths above approximately 5 µm.In this work, we propose InAsSb:Si/GaSb nanostructures as SEIRA and SPR substrates for an application in biosensing devices. InAsSb nanoantennas on GaSb substrates have been prepared using photolithography and wet chemical etching by a citric acid: hydrogen peroxyde solution or alternatively, by interferential lithography and reactive ion etching, especially to reduce the lattice parameter. An optical characterization of the structures was performed by FTIR spectroscopy, supported by numerical finite-difference time-domain (FDTD) calculations which were also applied to study the impact of geometrical parameters on the optical response. Notably, two types of structure designs were proposed: one-dimensional periodic gratings and two-dimensional arrays of rectangular shaped nanoantennas which provide localized surface plasmon resonances (LSPR) in both polarization directions contrary to the gratings and enable hence a dual band optical response. SPR sensing and SEIRA have successfully been demonstrated using both types of structures, with proof-of-concept analytes such as different polymers and the aromatic compound vanillin with absorption features at high IR wavelengths. A bulk sensitivity in the range of 10² to 10^3 nm/RIU was reached. The vibrational signals increased of factors ranging between approximately 1.2-5.7, and the SEIRA enhancement was estimated to be in the range of 10^3 to 10^4 for the rectangular nanoantenna arrays
Reymond-Laruinaz, Sébastien. "Biomolécules et systèmes nanostructurés : caractérisation par spectrométrie Raman exaltée de surface (SERS)." Thesis, Dijon, 2014. http://www.theses.fr/2014DIJOS023/document.
This work addressed the study of several kinds of nanostructured systems, biomolecules and inorganic thin films, mainly by Surface Enhanced Raman Spectroscopy (SERS). The aim was to investigate the structure and the chemical bonds. Transmission electron microscopy (TEM) was also used to complete the structural characterization of the different samples.Firstly, the study was conducted on molecules of biological interest. The aim was to study the interaction between silver nanoparticles and proteins. With this aim, silver nanoparticles bioconjugated with different proteins (hemoglobin, cytochrome C, BSA and lysozim) were synthesized. SERS results allowed concluding that proteins are chemisorbed on the silver nanoparticules surface. SERS was also used in the low frequency range to characterize the structure of thin deposits of caffeine, a molecule of pharmaceutical interest.Raman spectroscopy and SERS were also used to study nanostructured TiO2:Au thin films. The first stages of the growth of gold nanoparticles in Au doped TiO2 thin films under annealing treatments were studied by low frequency Raman spectroscopy and TEM. Finally, it was shown that SERS effect can be used for the characterization of ultra-thin TiO2 films. With this aim, ultra-thin TiO2 films were deposited by Atomic Layer Deposition on Si substrates functionalized with gold nanoparticles and studied by SERS
Polovinkin, Vitaly. "Utilisation des amphipols pour les études de spectroscopie Raman exaltée de surface et de cristallographie aux rayons X appliquées aux protéines membranaires." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENY069.
Amphipols (APols) have become important tools for the stabilization, folding, and in vitro structural and functional studies of membrane proteins (MPs). MPs are the main functional units of biomembranes and represent roughly one-third of the proteins encoded in the genome. The first part of my work was dedicated to crystallization of a MP trapped by APol. Direct crystallization of MPs solubilized in APols would be of high importance for structural biology. However, despite considerable efforts, it is still not clear whether MP/APol complexes can be used to form well-ordered crystals suitable for X-ray crystallography. The first major goal of this PhD thesis work was to show that APol-trapped MP can be crystallized in meso. To perform it we utilized special, flexibly adjustable for a certain MP, interconnected amphiphilic bilayers (IAB) approach which has been recently developed in our laboratory. We used bacteriorhodopsin (BR) trapped with APol A8-35 as a model system for our crystallization studies. The first obtained crystals diffracted to 3 Å, while a new developed type of high throughput nanovolume crystallization, exploiting dry precipitants, shifted the observed X ray diffraction peaks beyond 2 Å. The structure of BR was solved to 2 Å and found to be indistinguishable from previous structures obtained with a detergent-solubilized protein. We suggest that the proposed protocol of in meso crystallization is generally applicable to APol-trapped MPs.The second, to a certain extent, complementary part of the present work was related to application of APols to the surface-enhanced Raman scattering (SERS) studies of MPs. SERS spectroscopy has been developed dramatically since its discovery in the 1970s. It is a powerful analytical tool for selective sensing of molecules adsorbed onto noble metal nanoparticles (NPs) and nanostructures, including at the single molecule (SM) level. Unfortunately, MPs studies are far away from the main stream of SERS applications due to the great handling difficulties resulting from the amphiphilic nature of MPs. The ability of APols to trap MPs and keep them soluble, stable and functional opens the way for highly interesting applications of SERS studies, possibly at the SM level. Thus, the second goal of this PhD thesis work was to prove our concept of feasibility of SERS with MPs trapped by APols. Using the same as in the crystallization studies model BR/A8-35 complexes and silver NP aggregates, the task was fulfilled to a degree enough to start with the SERS studies of MPs.The first chapter of the PhD thesis begins with general information about the importance of MP studies and the problems with their handling. Further in this chapter, a brief overview of APols, their properties and applications is presented. The largest part of the “Introduction” is dedicated to main points of different MP crystallization approaches and Raman spectroscopy, in particular SERS spectroscopy, and their applications to proteins. The end of the “Introduction” part presents the conclusions about APol application for X-ray crystallography and SERS spectroscopy studies of MPs, setting the main goals for the present work. The “Materials and methods” chapter consists of detailed description of the materials and protocols used in this study. The results of crystallization and SERS studies and their interpretations are presented as two different parts in the last “Results and discussions” chapter. The “Conclusions and perspectives” sections accompany each of these parts
Siskova, Karolina. "Elaboration de nouvelles nanostructures d'Argent, obtenues par abblation laser, pour caractériser des macro- et biomolécules par spectroscopie Raman exaltée par effet de surface." Paris 6, 2006. http://www.theses.fr/2006PA066509.
Akanny, Elie. "Développement d’une méthode d’analyse de bactéries par Spectroscopie Raman Exaltée de Surface : application à la caractérisation de probiotiques microencapsulés pour le ciblage colique." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1277.
For their specific colonic delivery after oral administration, probiotics have to deal with the deleterious conditions of the gastro-intestinal tract that could alter their viability or functionality. Indeed, the quantity of viable microorganisms reaching the colon is often insufficient to provide the desired beneficial effect, namely, to maintain or restore the functions of the intestinal microbiota. To resolve this problem, the microencapsulation technology was considered. One aim of this project was thus to develop an encapsulation system for the colonic delivery via the oral route of the Lactobacillus rhamanosus GG (LGG), indicated for the treatment and the prevention of antibiotic-associated diarrhea. The development of such system requires a reliable quantification method of the bacteria to determine formulation characteristics such as encapsulation efficiency or release kinetics. The conventional counting method, using plating and culturing, is the most widely used method to this end but it appears tedious and above all time consuming. Due to its rapidity and simplicity, Surface Enhanced Raman Spectroscopy (SERS) technic, allowing to provide a high enhancement of Raman scattering from molecules adsorbed on a nanostructured noble metal surface (silver, gold), has been investigated as an alternative. SERS quantification method of LGG was therefore developed and applied to characterize the formulated encapsulation system. Microparticles encapsulating LGG were obtained by the spray-drying of an aqueous feed solution containing an enteric coating polymer and a protective agent of bacteria against the harmful effect of dehydration stress. A high cell viability was thus achieved after process. The protection of LGG strain against simulated gastrointestinal conditions, provided by the encapsulation matrix, attests that the developed encapsulation system is suitable for its use as a carrier for the specific colonic delivery of LGG via the oral route
Guillot, Nicolas. "Propriétés optiques de nanoparticules métalliques et application aux nanocapteurs par exaltation de surface." Phd thesis, Université Paris-Nord - Paris XIII, 2012. http://tel.archives-ouvertes.fr/tel-00844312.
Prado, Enora. "Détection de l’ADN par spectrométrie de diffusion Raman exaltée de surface couplée à la microfluidique." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14348/document.
This work deals with the development of an original label-free method for free bases proportions detection and quantification of nucleic acids. The surface enhanced Raman spectroscopy (SERS) allowed obtaining the specific spectral signature of characteristic nucleotides of RNA (adenosine, cytosine, guanosine and uridine), using silver colloids as SERS substrate and MgCl2 addition as aggregating agent. Then, the condition detection have optimizing to establish a label-free quantification protocol of free nucleobases proportion by SERS spectroscopy. The detection limits obtained are order of few picomoles. The reproducibility improvement of SERS detection requires the precise control of time reaction (adsorption and aggregation), which could be control thanks to microfluidic chips use. We have implemented two different microfluidic chips, one based on single-phase flows and one other based on droplets generation. The analyzed species are containing in droplets, allowing in situ detection by spectroscopy SERS of various nucleotides
Davies, P. R. "Reactions of molecules at surfaces studied by photoelectron and electron energy loss spectroscopies." Thesis, Cardiff University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305213.
Losquin, Arthur. "Surface Plasmon modes revealed by fast electron based spectroscopies : from simple model to complex." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00919765.
Guilment, Jean. "Contribution à l'étude des processus photographiques dans les halogénures d'argent par spectrométrie Raman et de fluorescence : influence de produits stabilisateurs et antivoiles, relation avec l'effet Raman exalté de surface (SERS)." Paris 6, 1986. http://www.theses.fr/1986PA066287.
Tournier-Colletta, Cédric. "Etude par spectroscopies d'électrons d'interfaces métalliques et semiconductrices." Thesis, Nancy 1, 2011. http://www.theses.fr/2011NAN10109/document.
This thesis is devoted to the electronic properties of low-dimensional systems based on metal and semiconducting materials. The first part deals with the Shockley state confinement in Ag(111) nanostructures, by means of very-low temperature (5 K) STM/STS measurements. We study the electronic structure and spatial distribution of the confined modes. Then the discrete nature of the electronic spectrum allows one to yield the quasiparticule lifetime. A Fermi-liquid behaviour is evidenced and we show that the dominant decay mechanism is attributed to the electron-phonon coupling. The extrinsic contribution arising from the partial confinement of the electronic wave is obtained as well. A scaling law with the nanostructure width is demonstrated, from which we deduce a higher reflection amplitude than in monoatomic islands. In the second part of the thesis, we study semiconducting ultra-thin films produced by alkali (K, Rb, Cs) deposition on the Si(111):B-[root of]3 surface. This work solves the controversy concerning the ground state of this system, and especially the nature of the 2[root of]3 surface recontruction obtained at saturation coverage. Prior understanding of the crystallographic structure allows to elucidate the electronic properties. We show that a one-electron picture, leading to a band insulator scenario, gives a good description of the system, in spite of strong polaronic effects. This conclusion results from an in-depth, combined study of complementary techniques (LEED, ARPES, XPS, STM/STS and DFT calculations)
Ljungberg, Mathias P. "Theoretical modeling of x-ray and vibrational spectroscopies applied to liquid water and surface adsorbates." Doctoral thesis, Stockholm : Department of Physics, Stockholm University, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-38868.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Manuscript. Paper 5: Manuscript. Paper 6: Manuscript.
Beffara, Flavien. "SERS biosensors based on special optical fibers for clinical diagnosis." Thesis, Limoges, 2021. http://www.theses.fr/2021LIMO0009.
Despite important breakthroughs in biosensing, we are still in need of new sensors that would facilitate the early detection of severe diseases such as cancer. Classical tissue biopsy remains the gold standard in many cases. Although this approach has shown its potential, it remains invasive for the patients and the detection techniques are either tedious or lack the sensitivity to detect the disease at an early stage. Raman spectroscopy has demonstrated its interests for biosensing. Its ability to characterize the chemical nature, structure and the orientation of an analyte makes it an ideal candidate. The sharp Raman peaks of a molecule can be seen as a true fingerprint. Regrettably, Raman scattered signal is extremely weak. This limitation was overcome by surface enhanced Raman spectroscopy (SERS), since it drastically increases the Raman scattered signal while maintaining the sharp peak of the fingerprint spectrum of a molecule. Unfortunately, most of the current SERS substrates are 2D nano-roughened metal surfaces or colloidal nanoparticles, which lack the sensitivity and reliability in measurement with poor repeatability and reproducibility in the data. In the recent years, special optical fibers have been used as SERS platforms. They feature holes that run along their entire length. These holes allow for the analyte to be incorporated inside the fiber. Thus, such platform represents a promising alternative to planar substrates since the analyte and the excitation light can interact for longer length inside the fibers. In addition, optical fibers are very flexible, compact and allow for low-loss light guiding. Therefore, such fiber sensors exhibit the outstanding detection abilities of SERS, the advantages of optical fibers and improved sensitivity and reliability. In this manuscript, we aim to create a biosensing platform that could be routinely used in a clinical setting. For that, we propose to optimize the features of an already reported fiber topology. This allows us to increase its sensitivity while simultaneously improving its reliability and practicability. With this improved sensor, for the first time, we could detect the biomarker for ovarian cancer in clinical cyst fluids, which allowed us to differentiate the stage of the cancer. Subsequently, we propose a novel fiber topology, specifically designed to further increase the sensitivity of SERS-based fiber probes. This is achieved by increasing the surface of interaction compared to standard fiber sensors. For that, the core diameter is significantly increased and the amount of light that interacts with the analyte is precisely controlled. We envision that such functionalized fiber sensors could be incorporated inside a biopsy needle to create a two-in-one sensor for body fluid collection and readout that can eventually overcome the limitations associated with existing biopsy needle platforms, which demands for two-step sample collection and readout
Hobro, Alison J. "Structural investigations of RNA through the application of Raman, Raman optical activity and surface enhanced spectroscopies." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491481.
Wu, Tsunghsueh Shannon Curtis. "Surface plasmon assisted spectroscopies and their application in trace element analysis, the study of biomolecular interactions, and chemical sensing." Auburn, Ala., 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SUMMER/Chemistry_and_Biochemistry/Dissertation/Wu_Tsung%20Hsueh_20.pdf.
Shao, Lei. "Surface chemistry and structural studies of photosystem II using UV-VIS and fluorescence spectroscopies and atomic force microscopy." Thèse, Trois-Rivières : Université du Québec à Trois-Rivières, 1998. http://www.uqtr.ca/biblio/notice/resume/03-2190303R.html.
Résumé en fraçais. Le résumé et la table des matières sont disponibles en format électronique sur le site Web de la bibliothèque. CaQTU Bibliogr. : f. [135]-167.
RANGAN, Sylvie. "Réactivité des nitriles sur la surface Si(001)-2x1, étudiée par spectroscopies de photoémission, d'absorption X et microscopie tunnel." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2004. http://tel.archives-ouvertes.fr/tel-00010268.
Cherif, Hadj Ahmed. "Torréfaction de la biomasse lignocellulosique prétraitée aux liquides ioniques - Propriétés physico-mécaniques et analyse comparative par spectroscopies de surface." Thesis, Université Laval, 2014. http://www.theses.ulaval.ca/2014/30581/30581.pdf.
The heat treatment of wood in a gas atmosphere is a process that aims to improve the properties of wood. Indeed, treated wood possesses improved dimensional stability, reduced hygroscopic nature and resistance to degradation by various factors (fungi, insects). The main disadvantage of the method is the long duration of treatment. This work explores the possibility of using ionic liquids for the treatment of wood as they have the particularity to accelerate the decomposition of the main wood constituents. Surface analysis and testing of physical and mechanical properties were performed on treated wood. The surface analysis showed that ionic liquids have contributed to the degradation of lignin as well as the development of the hydrophobic character of the wood. The physical and mechanical tests have meanwhile revealed that lower moisture and water absorption contents, decreased the swelling and mechanical properties.
Vandenborre, Johan. "Etude multi-échelle des mécanismes d'interaction des ions aquo uranyle avec les surfaces de l'oxyde de titane (poudres et monocristaux)." Phd thesis, Université Paris Sud - Paris XI, 2005. http://tel.archives-ouvertes.fr/tel-00011473.
Aybeke, Ece Neslihan. "Study of the dynamics of biomolecules by high speed atomic force microscopy and surface enhanced Raman spectroscopy." Thesis, Dijon, 2015. http://www.theses.fr/2015DIJOS023/document.
This thesis focuses on the coupling of High–Speed Atomic Force Microscopy (HS-AFM) and Surface Enhanced Raman Spectroscopy (SERS) for biomolecule analysis. We have designed a fabrication protocol to manufacture “SERS-active” substrates. The efficacy of gold, silver and gold-silver bimetallic crystalline nanoparticle substrates were evaluated. We have investigated the impact of optical and morphological features of the substrates on Raman signal intensity by analyzing well-known samples such as bipyridine ethylene and methylene blue molecules. We took an interest in three distinct biological problematics with HS-AFM and SERS analyses. First, we have detected the chemical signature of cytochrome b5 protein. This study was followed by the investigation of conformational changes of small heat shock leuconostoc oenos Lo 18 protein in function of pH level and concentrations. The last application consists to the analyse a membrane and a virus interaction. In order to realize simultaneous Raman/AFM analysis, we have adapted our fabrication protocol to cover the surface of commercial AFM probes by crystalline gold nanoparticles. Tip – Enhanced Raman Spectroscopy (TERS) studies were performed on molybdenum disulfide to evaluate the quality of TERS probes. In the last part of this work, we have designed a new setup to combine Ando’s HS-AFM setup with Raman spectroscopy. We present the modifications that have been carried out and the challenges that we have encountered
Lourenço-Martins, Hugo. "Experiment and theory of plasmon coupling physics, wave effects and their study by electron spectroscopies." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS284/document.
Surface plasmons (SP) are electromagnetic waves propagating at the interface between two media typically a metal and a dielectric. SPs can confine electromagnetic fields in very short volumes (typically one to few nanometers), well below the light diffraction limit. This property has a tremendous number of applications ranging from fundamental physics (e.g. quantum optics) to applications (e.g. cancer therapy). However, the price to pay is that SPs suffer from huge ohmic losses in the metal which leads to very short lifetimes (typically few femtoseconds). Theoretically, this presence of dissipation dramatically hardens the theoretical description of SPs. Another consequence of the sub-wavelength confinement of light associated with SPs is that their observation requires a nanometric resolution - which excludes the use of standard optical techniques. Yet, the scanning transmission electron microscope (STEM) is a particularly suitable tool to study SPs as it employs fast electrons with typical wavelength from 1 to 10 picometers. Thus, the last decade has seen the tremendous development of electron-based spectroscopies applied to nano-optics such as electron energy loss spectroscopy (EELS), cathodoluminescence spectroscopy (CL) or STEM- Hanbury Brown and Twiss interferometry (HBT). In this thesis, I explored different open problems of plasmonics and nano-optics under the scope of electron microscopy and spectroscopies. In chapter 3, I develop a formalism taking into account both the quantum and relativistic nature of EELS experiments using elements of quantum field theory. In chapter 4, I apply the latter formalism to the case of EELS measurements of SPs using electrons with shaped phase. In chapter 5, I give several theoretical and experimental results on coupling experiments involving SPs. Particularly, I demonstrate a counterintuitive type of coupling, the so-called self- hybridization which is a consequence of the non-Hermitian nature of the LSP eigenproblem and draw analogy with open quantum system. Finally, in chapter 6, I discuss the recent result on vibrational EELS in monochromated STEM
Troc, Nicolas. "Étude des propriétés optiques de nanoparticules d’argent sondées par spectroscopies optique et électronique." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1194/document.
The aim of this thesis is to study quantum effects appearing in very small metallic clusters caused by the increasing surface/volume ratio and the discretization of the electronic structure. Investigating effects such as size dependencies demand a very high quality of the studied nanoparticles, monodisperse in the ideal case. We fabricate nanostructures by embedding silver clusters generated in a magnetron source in solid matrices, such as silica or alumina. This technique gives us full and independent control over the particle composition, size and concentration. A quadrupole mass spectrometer is used as a size filter to obtain a more precise and narrow distribution.Samples have been characterized with two complementary methods: optical transmission spectroscopy of ensembles of particles and electron energy loss spectroscopy (EELS) on single particles using a scanning transmission electron microscope. Although these two tools are conceptually different, they both measure the plasmonic resonances of metal nanoparticles. The objective of this work is to link theory and experiment in these two methods in order to understand how the physical properties of these small noble metal clusters are affected by quantum effects
Chaigneau, Marc. "Imagerie et spectroscopies en champ proche optique : de la nano-sonde à la caractérisation de matériaux." Phd thesis, Université de Nantes, 2007. http://tel.archives-ouvertes.fr/tel-00274746.
proche optique, mais également l'émergence de capteurs moléculaires basée sur l'excitation de plasmons de
surface. Ce travail de thèse est consacré au développement de nano-sondes à base de fibres optiques destinées à ces
deux applications.
Après un état de l'art des différents procédés de la littérature, ce travail aborde une nouvelle approche pour
créer des nano-sondes optiques. La gravure chimique, pour créer une pointe à l'extrémité d'une fibre conique, est
premièrement optimisée. Les étapes suivantes sont réalisées dans un dispositif plasma original, basé sur une
décharge en régime de cathode creuse cylindrique. Pour finaliser la fabrication des sondes, les pointes métallisées
sont ouvertes in situ avec une micro-étincelle obtenue via une décharge couronne en configuration pointe-plan.
Notre microscope est ensuite détaillé et une étude paramétrique est menée afin d'optimiser la formation des
images, les capacités de résolution du sont discutées. A titre d'exemple, le microscope est ensuite appliqué à la
science des nano-matériaux, et quelles pistes d'investigation de nano-structures sont explorées, ainsi que le
potentiel de spectroscopie Raman en champ proche.
La spectroscopie résonante des plasmons de surface est aussi abordée. Les sondes spécialement modifiées
sont ici destinées à la détection moléculaire en milieu aqueux. Les capteurs ainsi élaborés sont testés dans des
microvolumes de solution, et leur capacité d'exaltation du signal Raman est présentée.
Van, Loon Lisa Lauralene. "Uptake of short-chain alcohols by sulfuric acid solutions using raman and vibrational sum frequency spectroscopies, and atmospheric implications." The Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=osu1174323601.
Cremel, Sébastien. "Contribution à l’étude des interactions ions-surfaces : application aux systèmes Se(IV), Se(VI), U(VI) sur TiO2 rutile et Eu(III) sur dickite." Thesis, Nancy 1, 2007. http://www.theses.fr/2007NAN10085/document.
Oxo-anions such as selenite/selenate (SeO32-/ SeO42-) and oxo-cationss such as uranyl (UO22+) are contaminants found in ultimate nuclear wastes (79Se) which could be stored in deep geological media. Furthermore, selenium mobile species can be found in high amount in some polluted soils. Adsorptions of selenite and selenate were studied on a model oxide surface, namely rutile TiO2. The final goal was to find out possible differences in reactivity among crystallographic faces and try to extrapolate the results to the powder behaviour. The goal of these studies was to use spectroscopic characterizations and batch experiments in order to propose surface complexes. As our interest is focused on the chemistry of the water/oxide interface, surface specific methods are thus required. Techniques used in this work are Angle Resolved X-Ray Photoelectron Spectroscopy, Near-Field Raman Spectroscopy (NFRS), Surface Second Harmonic Generation (SSHG), and Atomic Force Microscopy (AFM). Batch experiments were performed on powders, electrokinetics measurements, sorption edge curves and sorption kinetics curves were also realized. The influence of the salt used for adjusting the ionic strength (NaClO4 and NaCl) and, as titanium dioxide exhibits strong photocatalytic properties, the influence of sunlight were also studied. A photoreduction processus from Se(VI) to Se(IV) was evidenced. The second part of this manuscript presents some exploratory works dealing with innovative spectroscopies like Near-Field Luminescence applied to the study of Eu3+ interaction with an aluminate glass and a model clay : dickite
Le, Liepvre Sylvain. "Supramolecular self-assemblies for plasmonics : a bottom-up approach to efficient photonic nanodevices." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS330/document.
In this work, we have studied thephotonic and vibrational properties of selfassembled molecular monolayers on graphene and the possibility to use perylene self-assembled multilayers as a gain medium for plasmon amplification. Graphene, as a transparent and conductive material, has offered for the first time to correlate the self-assembly structure as deduced from scanning tunneling microscopy to photonic properties as analyzed by optical and Raman spectroscopy measurements. By comparing several self-assembled dyes on graphene we have shed lighton how intermolecular and dye-graphene interactions modify the absorption spectrum of the adsorbed dye.Fast Förster and Dexter energy transfer from the adsorbed dyes to the graphene layer prevent any radiative decay of the dye.Nevertheless, we have demonstrated the first fluorescent non-covalent functionalization of graphene by a supramolecular self-assembled monolayer using a spacer approach.We have exploited the fast dye fluorescence quenching by graphene to study Raman spectra of self-assembled dye on graphene, and we have shown the appearance of a coupled vibrational mode between the adsorbed molecules and the graphene substrate. We have demonstrated the strong couplingregime between a three-dimensional perylene self-assembly and a propagating plasmon polariton by optimizing the orientation and the organisation of the dye molecules compared to the electric field of the plasmon mode. We have shown that J-aggregated self-assembled gain media may theoretically lead to efficient gain media for plasmon amplification. However, we experimentally demonstrated that exciton-exciton recombination limits the achievable pumping rate at high fluences in such dense media
Mathieu, Claire. "Approche intégrée "spectroscopies électroniques et calculs ab-initio d'états de cœur excités" des modes d'adsorption de l'ammoniac et de diamines sur la surface Si(001)-2x1." Paris 6, 2009. http://www.theses.fr/2009PA066287.
Eschimese, Damien. "Design, fabrication, and characterization of TIP-enhanced Raman spectroscopy probes based on metallic nano-antennas." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1I020/document.
Since the start of the 2000s the evolution of tip-enhanced Raman spectroscopy (TERS) has enabled the simultaneous measurement of localized structural, molecular, and physicochemical properties. TERS technology combines scanning probe microscopy -- atomic force microscopy (AFM) -- with near field optical microscopy. The combined technique is referred to as AFM-TERS. The technique harnesses and exploits the generation of surface plasmons on metal surfaces. These plasmons lead to the generation of confined electromagnetic waves in a sub-wavelength volume at the very tip of the AFM-TERS probe. The main technological challenge today is the design and optimization of an AFM-TERS probe having nanometer-sized dimensions -- and the controlled, reproducible batch fabrication of such structures. The objective of the work presented in this PhD thesis was to design, fabricate, and characterize a new type of AFM probe capable of bettering the current state-of-the-art performances. The PhD was carried out in collaboration with HORIBA and funded partly by a French ‘CIFRE’ grant. In order to meet these objects, comprehensive numerical modelling led to the design of an optimized metal nanostructuring having maximum electromagnetic exaltation -- placed at the extremity of a silicon-based AFM cantilever. A new combined micro and nano fabrication process was developed to achieve this -- to be performed using the existing equipment found in the IEMN cleanroom. The process encompasses techniques such as masking using electron beam (ebeam) lithography and UV photolithography, thermal evaporation of metals and ‘lift-off’ techniques, and highly-controlled dry etching of small silicon mesas structures and deep etching for MEMS cantilever releasing. The process enables the batch-fabrication manufacture of AFM-TERS probes containing matter on the millimeter scale (the silicon probe support), the micrometer scale (the silicon cantilever), and the nanometer scale (the combined metallic disk and cone having sub-wavelength dimensions). This method allows nanostructuring on the optical/plasmonic behavior of TERS probes, the key factor which will lead to higher performance in TERS. Finally, a further study concerning the inclined evaporation of metallic nanostructures via an ebeam-derived lithographic shadow mask was performed in order to control the size and shape of the nanostructuring. The study proved this approach to be feasible. Furthermore, numerical modelling of such structures suggests that they are potential original candidates for both TERS and SERS (surface-enhanced Raman spectroscopy)
Mathieu, Claire. "Approche intégrée "Spectroscopies électroniques et Calculs ab-initio d' états de c oeur excit és" des modes d'adsorption de l'ammoniac et de diamines sur la surface Si(001)-2 x1." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2009. http://tel.archives-ouvertes.fr/tel-00796706.
Kaya, Zeynep. "Controlled and localized synthesis of molecularly imprinted polymers for chemical sensors." Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2220.
Molecularly imprinted polymers (MIPs), also referred to as plastic antibodies, are synthetic biomimetic receptors that are able to bind target molecules with similar affinity and specificity as natural receptors such as enzymes or antibodies. Indeed, MIPs are used as synthetic recognition elements in biosensors and biochips for the detection of small analytes and proteins. The molecular imprinting technique is based on the formation of specific recognition cavities in polymer matrices by a templating process at the molecular level. For sensor and biochip development, fast binding kinetics of the MIP for a rapid sensor response, the integration of the polymers with transducers, and a high sensitivity of detection are among the main challenges. In this thesis, the above issues are addressed by developing MIP/gold nanocomposites by grafting MIPs on surfaces, using dedicated techniques like atom transfer radical polymerization (ATRP) which is a versatile controlled radical polymerization (CRP) technique. Theses ophisticated CRP techniques, are able to greatly improve the polymeric materials. The use of ATRP in the MIP field has been limited so far due to its inherent incompatibility with acidic monomers like methacrylic acid (MAA), which is by far the most widely used functional monomer. Herein, a new method is described for the MIP synthesis through photo-initiated ATRP using fac-[Ir(ppy)3] as ATRP catalyst. The synthesis is possible at room temperature and is compatible with acidic monomers. This study considerably widens the range of functional monomers and thus molecular templates that can be used when MIPs are synthesized by ATRP. The proposed method was used for fabrication of hierarchically organised nanocomposites based on MIPs and nanostructured metal surfaces containing nanoholes or nanoislands, exhibiting plasmonic effects for signal amplification. The fabrication of nanometer scale MIP coatings localized on gold surface was demonstrated. Optical transduction methods, namely Localized Surface Plasmon Resonance (LSPR) and Surface Enhanced Raman Spectroscopy (SERS) were exploited and shown that they hold great promise for enhancing the limit of detection in sensing of biologically relevant analytes including proteins and the drug propranolol
Handick, Evelyn [Verfasser], Marcus [Akademischer Betreuer] Bär, Dieter [Akademischer Betreuer] Schmeißer та Bernd [Akademischer Betreuer] Rech. "Surface and interface characterization by X-ray and electron spectroscopies - revealing the peculiarities of Cu(In,Ga)Se₂ chalcopyrite and CH₃NH₃PbI(₃-ᵪ)Clᵪ perovskite-based thin film solar cell structures / Evelyn Handick ; Marcus Bär, Dieter Schmeißer, Bernd Rech". Cottbus : BTU Cottbus - Senftenberg, 2017. http://d-nb.info/113690445X/34.