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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Plasmon Directed Chemical Reactivity and Nanoparticle Self-Assembly

See, Erich M. 25 April 2017 (has links)
Nanotechnology has advanced to the point that nanoparticles can now be fabricated in a broad variety of shapes from a wide range of materials, each with their own properties and uses. As the list of manufacturable particles continues to grow, a new frontier presents itself: assembling these existing nanoparticles into more complicated nanoscale structures. The primary objective of this thesis is to demonstrate and characterize one such method of nanoscale construction, the plasmonically directed self-assembly of gold nanospheres onto both silver nanospheroids and gold nanorods. At the heart of this research is a the use of a photocleavable ligand (1-(6-Nitrobenzo[d][1,3]dioxol-5-yl)ethyl(4-(1,2-Dithiolan-3-yl)butyl) carbamate), which is capable of forming a photoreactive self-assembly monolayer (SAM) on gold and silver surfaces. After photoactivation, this SAM becomes positively charged at low pH, allowing it to electrostatically bind with negatively charged gold nanospheres (or other negatively charged nanoparticles). In this thesis, I describe both a secondary photoreaction that this ligand is capable post-photocleavage, which removes the ligand's ability to bind to negatively charged gold nanospheres, allowing for, among other assembly methods, reverse photopatterning. I further show that this photocleavable ligand can be used in conjunction with gold nanospheres to create aligned, metal structures on silver nanospheroid surface by exposure to linearly polarized UV light. Similarly, I also demonstrate how the ligand can be used to preferentially bind gold nanospheres to the ends of gold nanorods with the use of ultrafast femtosecond pulsed 750 nm laser light, making use of multi-photon absorption. Both methods of self-assembly, as well as the secondary photoreaction, are dependent on the plasmonics of the metal nanoparticles. This thesis also goes into the backgrounds of plasmonics, plasmonically mediated catalysis, self-assembly, and photocleavable chemicals. / Ph. D. / Nanotechnology has advanced to the point that nanoparticles can now be fabricated in a broad variety of shapes from a wide range of materials, each with their own properties and uses. As the list of manufacturable particles continues to grow, a new frontier presents itself: assembling these existing nanoparticles into more complicated nanoscale structures. The ability to build and design such structures further advances the use of nanotechnology for medical and industrial applications. In this thesis, I describe and demonstrate a method of nanoparticle self-assembly developed by our group which uses the unique optical properties of metallic nanoparticles in conjunction with a light-activated binding chemical to control and direct the assembly of gold nanoparticles onto a silver nanosphere or gold nanorod base. The preliminary results for both of these techniques are highly promising, and I describe them in detail. I furthermore explore a secondary light-driven reaction our light-activated chemical is capable of. This secondary reaction can prevent particle binding, broadening the applications and techniques of the lightactivated binding chemical.
242

Optical Nanoantennas Integrated with 3D Microelectrode Arrays: Hybrid Photonic-Electronic Modalities for Nano-Bio Interfacing

Mejia, Elieser A. 08 November 2024 (has links)
The human body is dynamic and understanding such complexity for accurate diagnostics and therapies remains a challenge due to lack of minimally-invasive biotechnologies capable of long-term measurements of various biochemical and bioelectrical signals simultaneously from single cells to cell networks. Biocompatibility is a major challenge but recent advancements in micro- and nano-fabrication has shown that patterned protruding pillars from surfaces at the micro- and nano-scale can mimic intrinsic biological structural cues to trigger strong cell adhesion, engulfment, and growth, providing a means by which to engineer the biocompatibility for controlled cell-device bio-interfaces. Here, we sought to leverage the unique biocompatibility of engineered three-dimensional (3D) features with integrated biochemical and bioelectrical sensor arrays to create a multi-modal platform for complex systems biological research. For the biochemical sensor, we introduced a tunable optical nanoantenna that is driven wirelessly by incident laser light (photons) to create a highly localized electric field capable of enhancing the photon scattering rate of nearby chemical bonds, a unique signature that provides a means to fingerprint the local biomolecular ensembles depending on the color of detected scattered photons. By a novel scalable fabrication technique, we merged such nano-sensors with 3D micropillar electrode arrays to create a device with hybrid biophotonic and bioelectronic functionality. We revealed the unique optical properties by micro-reflectance measurements and numerical simulations and verified by spectroscopic measurements a million-fold enhancement to the scattered photon signature from a standard chemical monolayer. We showed favorable bioelectrical properties by electrochemical impedance spectroscopy and cyclic voltammetry, revealing a stable electrochemical interface and reduced resistance due to 3D geometry enabling improved transduction of electrical signals, useful for higher signal to noise ratios in bioelectrical measurements. Overall, we demonstrated the scalable fabrication and unique optical and electrical properties suitable for next generation multi-modal bio-interfacing platforms. / This work was supported by US AFOSR Young Investigator Award FA9550-18-1-0328, US AFOSR DURIP Award FA9550-19-1-0287, US NIST grant 70NANB18H201, and US NIST grant 70NANB19H163. / Master of Science / The human body is dynamic and understanding such complexity for accurate diagnostics and therapies remains a challenge due to lack of minimally-invasive biotechnologies capable of long-term measurements of various biochemical and bioelectrical signals simultaneously from single cells to cell networks. Biocompatibility is a major challenge but recent advancements in micro- and nano-fabrication has shown that patterned protruding pillars from surfaces at the micro- and nano-scale can mimic intrinsic biological structural cues to trigger strong cell adhesion, engulfment, and growth, providing a means by which to engineer the biocompatibility for controlled cell-device bio-interfaces. Here, we sought to leverage the unique biocompatibility of engineered three-dimensional (3D) features with integrated biochemical and bioelectrical sensor arrays to create a multi-modal platform for complex systems biological research. For the biochemical sensor, we introduced a tunable optical nanoantenna that is driven wirelessly by incident laser light (photons) to create a highly localized electric field capable of enhancing the photon scattering rate of nearby chemical bonds, a unique signature that provides a means to fingerprint the local biomolecular ensembles depending on the color of detected scattered photons. By a novel scalable fabrication technique, we merged such nano-sensors with 3D micropillar electrode arrays to create a device with hybrid biophotonic and bioelectronic functionality. We revealed the unique optical properties by micro-reflectance measurements and numerical simulations and verified by spectroscopic measurements a million-fold enhancement to the scattered photon signature from a standard chemical monolayer. We showed favorable bioelectrical properties by electrochemical impedance spectroscopy and cyclic voltammetry, revealing a stable electrochemical interface and reduced resistance due to 3D geometry enabling improved transduction of electrical signals, useful for higher signal to noise ratios in bioelectrical measurements. Overall, we demonstrated the scalable fabrication and unique optical and electrical properties suitable for next generation multi-modal bio-interfacing platforms.
243

Étude du confinement acoustique dans des nano-structures métalliques et semiconductrices par diffusion Raman basse fréquence / Acoustic confinement in metallic and semiconducting nanostructures studied by low frequency Raman spectroscopy

Girard, Adrien 11 July 2016 (has links)
Les spectroscopies de diffusion inélastique de la lumière (Raman/Brillouin) sont un outil versatile qui permet d'étudier les phonons thermiques de la matière à différentes échelles. Dans les milieux nano-granulaires, l'étude des phonons acoustiques dont la longueur d'onde est grande devant le diamètre D des grains (?/D >> 1) permet de caractériser l'élasticité macroscopique gouvernée par la loi du contact de Hertz. La validité de la loi de contact est étudiée pour des poudres d'oxyde constituées de nanoparticules sphériques d'une taille de quelques nanomètres. Lorsque la demi-longueur d'onde des phonons acoustiques devient égale à la dimension du confinement (diamètre D pour les sphères, épaisseur e pour une plaquette), la propagation n'est plus possible et un phénomène de résonance mécanique apparaît. La spectroscopie Raman basse fréquence a été utilisée pour caractériser les modes de vibration acoustique de nanoplaquettes semiconductrices habillées d'un « manteau » organique. Lorsque l'épaisseur est suffisamment faible (e ~1 nm) une forte déviation de la fréquence de résonance est observée par rapport au modèle de la plaquette libre, attribuée à la présence des molécules organiques et est interprétée par un effet nano-balance. Lorsque l'objet confinant est un nano-dimère métallique, une hybridation plasmonique et acoustique des nanoparticules ont lieu conjointement. L'excitation résonante du plasmon dimèrique permet d'observer à l'échelle d'un dimère unique la diffusion par les modes de vibration dipolaire hybridé l=1 ainsi que les modes non hybridés de moment angulaire l >2, interdits par les règles de sélection précédemment établies pour ce régime de taille / Inelastic light scattering spectroscopies (Raman/Brillouin) are a versatile tool to study thermal phonons at various scales. In nano-granular media, the study of acoustic phonons with a wavelength much greater than the grain diameter D (?/D >> 1) allows one to characterize the macroscopic elasticity governed by Hertz law of the contact. The validity of Hertz law is studied for powders made of oxide nanoparticles a few nanometers in diameter. When the phonon half-wavelength reaches the confinement dimension (diameter D for spheres, thickness e for plates) propagation is forbidden and mechanical resonances occur. Low frequency Raman spectroscopy has been used to characterize the acoustic resonances of semiconducting nanoplatelets “dressed” with an organic surfactant layer. When the thickness becomes thin enough (e ~ 1 nm), the resonance frequency is significantly downshifted compared to a free platelet, attributed to a mass load effect due to the organic molecules. When the confining object is a metallic nano-dimer, both plasmonic and acoustic hybridization occur at the same time. The resonant excitation of the dimeric plasmon allows one to observe down to single nano-object scale the inelastic scattering by dimer hybridized dipolar vibration modes l=1 as well as non-hybridized modes with higher angular momentum l >2, known to be Raman inactive in this size range according to previously established selection rules. Possibilities for a new plasmon-vibration coupling mechanism are discussed
244

Label-free plasmonic detection using nanogratings fabricated by laser interference lithography

Hong, Koh Yiin 02 January 2017 (has links)
Plasmonics techniques, such as surface plasmon resonance (SPR) and surface-enhanced Raman scattering (SERS), have been widely used for chemical and biochemical sensing applications. One approach to excite surface plasmons is through the coupling of light into metallic grating nanostructures. Those grating nanostructures can be fabricated using state-of-the-art nanofabrication methods. Laser interference lithography (LIL) is one of those methods that allow the rapid fabrication of nanostructures with a high-throughput. In this thesis, LIL was combined with other microfabrication techniques, such as photolithography and template stripping, to fabricate different types of plasmonic sensors. Firstly, template stripping was applied to transfer LIL-fabricated patterns of one-dimensional nanogratings onto planar supports (e.g., glass slides and plane-cut optical fiber tips). A thin adhesive layer of epoxy resin was used to facilitate the transfer. The UV-Vis spectroscopic response of the nanogratings supported on glass slides demonstrated a strong dependency on the polarization of the incident light. The bulk refractive index sensitivities of the glass-supported nanogratings were dependent on the type of metal (Ag or Au) and the thickness of the metal film. The described methodology provided an efficient low-cost fabrication alternative to produce metallic nanostructures for plasmonic chemical sensing applications. Secondly, we demonstrated a versatile procedure (LIL either alone or combined with traditional laser photolithography) to prepare both large area (i.e. one inch2) and microarrays (μarrays) of metallic gratings structures capable of supporting SPR excitation (and SERS). The fabrication procedure was simple, high-throughput, and reproducible, with less than 5 % array-to-array variations in geometrical properties. The nanostructured gold μarrays were integrated on a chip for SERS detection of ppm-level of 8-quinolinol, an emerging water-borne pharmaceutical contaminant. Lastly, the LIL-fabricated large area nanogratings have been applied for SERS detection of the mixtures of quinolone antibiotics, enrofloxacin, an approved veterinary antibiotic, and one of its active metabolite, ciprofloxacin. The quantification of these analytes (enrofloxacin and ciprofloxacin) in aqueous mixtures were achieved by employing chemometric analysis. The limit of quantification of the method described in this work is in the ppm-level, with <10 % SERS spatial variation. Isotope-edited internal calibration method was attempted to improve the accuracy and reproducibility of the SERS methodology. / Graduate / 2018-02-17
245

Modélisation multi-échelle de systèmes nanophotoniques et plasmoniques / Multi-scale modelling of nanophotonic and plasmonic systems

Fall, Mandiaye 06 December 2013 (has links)
Les structures nanophotoniques sont généralement simulées par des méthodes de volumes, comme la méthode des différences finies dans le domaine temporel (FDTD), ou la méthode des éléments finis (FEM). Toutefois, pour les grandes structures, ou des structures plasmoniques métalliques qui nécessitent, la mémoire et le temps de calcul requis peuvent augmenter de façon spectaculaire.Les méthodes de surface, comme la méthode des éléments de frontière (BEM) ont été développées afin de réduire le nombre d'éléments de maillage. Ces méthodes consistent à exprimer le champ formé dans tout l'espace en fonction des courants électrique et magnétique à la surface de l’objet. Combinées avec la méthode multipôle rapide (FMM) qui permet une accélération du calcul de l'interaction entre les éléments lointain du maillage, de grands systèmes peuvent ainsi être manipulés.Nous avons développé, pour la première fois à notre connaissance, une FMM sur un nouveau formalisme BEM, basé sur les potentiels scalaire et vectoriel au lieu de courants électriques et magnétiques. Cette méthode a été montrée pour permettre une simulation précise des systèmes plasmoniques métalliques, tout en offrant une réduction significative des besoins de calcul. Des systèmes nanophotoniques complexes ont été simulés, comme une lentille plasmonique composé d'un ensemble de nanotubes d'or. / Nanophotonic structures are generally simulated by volume methods, as Finite-difference time-domain (FDTD) method, or Finite element method (FEM). However, for large structures, or metallic plasmonic structures, the memory and time computation required can increase dramatically, and make proper simulation infeasible.Surface methods, like the boundary element method (BEM) have been developed to reduce the number of mesh elements. These methods consist in expressing the electromagnetic filed in whole space as a function of electric and magnetic currents at the surface of scatterers. Combined with the fast multipole method (FMM) that enables a huge acceleration of the calculation of interaction between far mesh elements, very large systems can thus be handled.What we performed is the development of an FMM on a new BEM formalism, based on scalar and vector potentials instead of electric and magnetic currents, for the first time to our knowledge. This method was shown to enable accurate simulation of metallic plasmonic systems, while providing a significant reduction of computation requirements, compared to BEM-alone. Several thousands of unknowns could be handled on a standard computer. More complex nanophotonic systems have been simulated, such as a plasmonic lens consisting of a collection of gold nanorods.
246

Plasmonic Metasurfaces Utilizing Emerging Material Platforms

Krishnakali Chaudhuri (6787016) 02 August 2019 (has links)
<p>Metasurfaces are broadly defined as artificially engineered material interfaces that have the ability to determinately control the amplitude and phase signatures of an incident electromagnetic wave. Subwavelength sized optical scatterers employed at the planar interface of two media, introduce abrupt modifications to impinged light characteristics. Arbitrary engineering of the optical interactions and the arrangement of the scatterers on plane, enable ultra-compact, miniaturized optical systems with a wide array of applications (e.g. nanoscale and nonlinear optics, sensing, detection, energy harvesting, information processing and so on) realizable by the metasurfaces. However, maturation from the laboratory to industry scale realistic systems remain largely elusive despite the expanding reach and vast domains of functionalities demonstrated by researchers. A large part of this multi-faceted problem stems from the practical constraints posed by the commonly used plasmonic materials that limit their applicability in devices requiring high temperature stability, robustness in varying ambient, mechanical durability, stable growth into nanoscale films, CMOS process compatibility, stable bio-compatibility, and so on. </p> <p>Aiming to create a whole-some solution, my research has focused on developing novel, high-performance, functional plasmonic metasurface devices that utilize the inherent benefits of various emerging and alternative material platforms. Among these, the two-dimensional MXenes and the refractory transition metal nitrides are of particular importance. By exploiting the plasmonic response of thin films of the titanium carbide MXene (Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub>) in the near infrared spectral window, a highly broadband metamaterial absorber has been designed, fabricated and experimentally demonstrated. In another work, high efficiency photonic spin Hall Effect has been experimentally realized in robust phase gradient metasurface devices based on two different refractory transition metal nitrides –titanium nitride (TiN) and zirconium nitride (ZrN). Further, taking advantage of the refractory nature of these plasmonic nitrides, a metasurface based temperature sensor has been developed that is capable of remote, optical sensing of very high temperatures ranging up to 1200<sup>o</sup>C.</p>
247

Caractérisation de la chiralité optique dans des systèmes plasmoniques / Characterization of optical chirality effects in plasmonic systems

Pham, Kim Anh Aline 06 November 2018 (has links)
L'objectif de ce projet de thèse est de mettre en évidence des phénomènes de chiralité optique induits dans des systèmes plasmoniques. La manipulation des différents degrés de liberté de la lumière est mise en évidence par le biais de techniques expérimentales complémentaires basées sur la tomographie en polarisation, la microscopie à fuites radiatives et la microscopie en champ proche optique (SNOM). D'une part, nous rapportons une méthode de caractérisation non-invasive afin de révéler la présence conjointe de chiralité planaire et volumique au sein de métasurfaces plasmoniques. Pour décrire cette chiralité mixte, une généralisation du modèle de Kuhn est développée. D'autre part, nous démontrons deux dispositifs plasmoniques exploitant le couplage spin-orbite optique pour contrôler les moments angulaires de spin et orbitaux de la lumière. En particulier, le mécanisme réciproque de l'effet spin Hall optique est démontré à l'aide de nano-ouvertures en forme de T: la trajectoire des plasmons de surface est adressée dans le moment angulaire de spin des photons. Cette fonctionnalité est ensuite mise en œuvre dans une expérience de brouillage d'interférence. La génération de vortex plasmoniques est également réalisée par le biais de cavités spirales, dont la chiralité conditionne l'intensité et le moment angulaire orbital des vortex. Enfin, une preuve de concept sur la mesure de la densité locale d’états optique, façonnée par un environnement chiral, est démontrée à l'aide d'une sonde SNOM classique et quantique. Ce travail permet de connecter les grandeurs de densité et de flux de chiralité aux interactions lumière-matière. L'étude de la chiralité dans le contexte de la plasmonique ouvre des perspectives prometteuses dans la nano-manipulation optique, la séparation de molécules chirales et le contrôle de sources quantiques. / In this thesis, we aim at demonstrating chiral optical effects in plasmonic systems. The manipulation of the different degrees of freedom of light is evidenced by complementary experimental approaches based on polarisation tomography, leakage radiation microscopy and scanning near-field optical microscopy (SNOM). On one hand, we report on a non-invasive method to reveal the coexistence of surface and bulk chirality in plasmonic metasurfaces. Specifically, we extend the model of Kuhn to describe this chirality mixture. On the other hand, we demonstrate two plasmonic devices which rely on the optical spin-orbit coupling to control the spin and the orbital angular momentum of light. In particular, the reciprocal mechanism of the spin-Hall effect of light is shown using T-shaped nano-apertures: the trajectory of surface plasmons can be encoded in the spin of the photons. This which-path marker is then implemented in an interference erazer experiment. Plasmonic vortex generation is also reported in spiral cavities. The spiral chirality rules the intensity as well as the angular orbital momentum of the singular fields. Finally, as a proof of concept, we demonstrate using a conventional and quantum SNOM probe that the local density of optical states can be structured by a chiral environment. We also connect the density and flux chirality to light-matter interactions. Studying chirality in the context of plasmonics opens promising prospects in the optical nano-manipulation, chiral molecules discrimination and the control of quantum sources.
248

Demonstration of the spatial self-trapping of a plasmonic wave / Démonstration de l'autofocalisation d'une onde plasmonique

Kuriakose, Tintu 12 July 2018 (has links)
Cette thèse est une contribution au domaine de recherche de la plasmonique nonlinéaire, domaine émergent de l'optique. L'objectif principal est de démontrer expérimentalement l'autofocalisation d'une onde plasmonique.L'étude débute avec la fabrication et la caractérisation de guides plans en verre de chalcogénure de composition Ge-Sb-Se. Une technique basée sur la formation de solitons spatiaux est développée afin d’estimer leurs non-linéarités Kerr. Les propriétés optiques linéaires et non linéaires de ces guides sont étudiées aux longueurs d’onde de 1200 nm et 1550 nm.Des structures plasmoniques sont ensuite conçues pour propager des ondes hybrides plasmon-solitons avec des pertes de propagation modérées. Elles sont constituées des guides précédents recouverts de nanocouches de silice et d'or.Les caractérisations optiques par couplage plasmon-soliton révèlent une forte autofocalisation subie par l’onde qui se propage à l'intérieur de la structure plasmonique. Comme prévu par la théorie, le comportement est présent uniquement pour une lumière polarisée TM. Des résultats expérimentaux détaillés de cette autofocalisation exaltée par effet plasmonique sont présentés pour différentes configurations. Des simulations confirment les résultats expérimentaux obtenus.Cette démonstration fondamentale vient confirmer le concept d’autofocalisation assistée par plasmon tout en révélant un effet nonlinéaire très efficace. Cela ouvre de nouvelles perspectives pour le développement de dispositifs photoniques non linéaires intégrés ainsi que de nouveaux phénomènes physiques. / This dissertation contributes to the research area of nonlinear plasmonics an emerging field of optics. The main goal is to demonstrate experimentally the spatial self-trapping of a plasmonic wave.The study begins with the fabrication and the characterization of slab Ge-Sb-Se chalcogenide waveguides. A technique based on the formation of spatial solitons is developed to estimate their Kerr nonlinearities. Linear and nonlinear optical properties of the waveguides are studied at the wavelengths of 1200 nm and 1550 nm.Plasmonic structures are then designed to propagate hybrid plasmon-soliton waves with moderate propagation losses. They are constituted of the previous waveguides covered with nanolayers of silica and gold.Optical characterizations reveal a giant self-focusing undergone by the wave that propagates inside the plasmonic structure. The behavior is present only for TM polarized light as expected from theory. Detailed experimental results of this plasmon enhanced nonlinear self-trapping corresponding to different configurations are presented. Simulations confirm the obtained experimental results.This fundamental demonstration confirms the concept of plasmon-assisted self-focusing while revealing a very efficient nonlinear effect. This opens new perspectives for the development of integrated nonlinear photonic devices as well as new physical phenomena.
249

Exploration of how light interacts with arrays of plasmonic, metallic nanoparticles

Humphrey, Alastair Dalziell January 2015 (has links)
The content of this thesis is based upon the interaction of light with metallic nanoparticles arranged in different array geometries. An incident electric field (light) can force the conduction electrons of a metallic nanoparticle to oscillate. At particular frequencies, in the optical regime for gold and silver particles, absorption and scattering of the light by the particle is enhanced, corresponding to the particle plasmon resonance. The spectral position and width of the particle plasmon resonance of an isolated single particle may be tuned by adjusting its size and shape, thus changing the surface charge distribution. Periodic arrays of particles offer additional control over the frequency and width of the resonance attributed to the re-radiating (scattering) property of plasmonic particles. By fabricating arrays with a pitch comparable to the wavelength of an isolated single particle plasmon resonance, a coherent interaction between particles may be produced, known as surface lattice resonances (SLRs). The electromagnetic coupling between in-plane particle plasmon modes for different particle array geometries is explored through experiment and theory. Firstly, SLRs in square, hexagonal and honeycomb arrays are investigated by normal-incidence extinction measurements and compared to a simple-coupled dipole model. Secondly, to verify the nature of the coupling between the scattered electric field associated with particle resonances, the incident electric field polarization-dependence of the extinction of rectangular arrays and chains is studied. Thirdly, the optical response of square arrays with a symmetric two-particle basis is investigated, particularly the retardation of the scattered electric field between particles in a pair. Fourthly, square arrays with an asymmetric two-particle basis are fabricated to explore the symmetric (dipole moments of both particles are parallel) and anti-symmetric (dipole moment of both particles anti-parallel) SLRs, excited by normal-incidence light.
250

Propriétés optiques de colloïdes assemblés : plasmonique et confinement diélectrique / Optical properties of deterministic colloidal assemblies : plasmonics and dielectric confinement

Lecarme, Olivier 20 December 2011 (has links)
Les solutions colloïdales constituées de nanoparticules en solution sont une famille d'objets aux propriétés optiques uniques. Leur utilisation comme élement de base à la fabrication de composants optiques sublongueur d'onde pourrait permettre la naissance de nouvelles applications en particulier dans le domaine de l'optique intégrée et de la détection biologique. La manipulation de ces particules reste toutefois un défi en raison de leur taille et de leur dispersion aléatoire dans un milieu liquide. Dans ce contexte, nous avons réalisé des nouveaux composants optiques grâce au développement de techniques de fabrication basées sur la méthode d'assemblage capillaire assisté par convection. Deux types de structures ont été réalisés puis évalués en terme de comportement optique : les dimères métalliques d'Au et les microsphères diélectriques de polystyrène assemblées en chaînes ou en réseaux. Pour les dimères, une étude fondamentale a été effectuée sur les phénomènes plasmoniques régissant les propriétés optiques de ces objets. Leur potentiel en tant que détecteur ultrasensible SERS et nanoantenne à boîtes quantiques a ensuite été approfondi. Pour les microsphères, une étude sur la propagation et la diffusion des modes de galerie présents dans ces objets a tout d'abord été réalisée dans le but d'en faire des candidats pour la détection ultrasensible. Les propriétés de guidage de la lumière dans des assemblages en chaîne ont ensuite été traitées. Afin de compléter ce travail un dernier composant optique a été développé en complément des guides et capteurs colloïdaux déjà réalisés. Il s'agit d'une nouvelle génération d'émetteurs localisés conçus pour un usage large et versatile et qu'il est possible de définir comme microsource de lumière blanche. / Colloids -- e.g. nanoparticles in solution -- are objects that exhibit original optical properties. Their use as building block for fabrication of subwavelength optical components may allow novel applications in the field of integrated optics and biological detection. Anyway colloidal particles handling remains a challenge because of their small size and their random dispersion into a liquid medium. In this context, we created new colloidal optical components thanks to nanofabrication techniques based on the convective assisted capillary force assembly method. Two different kinds of structure were made and their optical behavior was studied: gold colloidal dimers and polystyrene dielectric microspheres assembled as chains or arrays. For the dimers, a fundamental study was performed on plasmonic phenomena that rule the optical properties of these objects. Next, their potential was evaluated in terms of ultrasensitive SERS sensor and also as optical nanoantenna of quantum dot emitters. For the microspheres, the propagation and scattering behaviors of whispering gallery modes that travel into the microspheres were first investigated. Their potential use as ultrasensitive sensors was also discussed. In addition, a second study was made on the guiding properties of linear microspheres chains. In order to complete this work, one last optical component was developped in addition to the fabricated colloidal waveguides and colloidal sensors. This component is a white light microsource that was designed for applications as a versatile localized emitter for integrated optics.

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