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Chen, Li. „Hybrid Silicon and Lithium Niobate Integrated Photonics“. The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429660021.
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Elancheliyan, Rajam. „Directed Assembly of Hybrid Colloids for Optics“. Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0139.
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Cette thèse est dédiée à la recherche d'une nouvelle voie de fabrication de métasurfaces optiques en utilisant des approches «bottom-up» basées sur la chimie en milieu liquide et l'auto-assemblage.Dans ce projet, nous utilisons une voie de formulation à base d'émulsion pour synthétiser des agrégats de nanoparticules d'or. La voie de formulation consiste à émulsionner une suspension de nanoparticules d'or dans l'eau en phase huileuse à l'aide de tensioactifs adaptés. Cette étape est suivie par l'évaporation contrôlée de l'eau des gouttelettes sous basse pression pour confiner les nanoparticules dans les amas finaux. La surface des nanoparticules d'or a été préalablement fonctionnalisée afin de conserver leurs propriétés de résonance plasmonique de surface dans l'assemblage final. La structure des agrégats, et plus précisément leur fraction volumique interne en or f, est contrôlée en faisant varier la masse molaire et la densité de surface du polymère de greffage. La structure finale des agrégats est étudiée en utilisant la diffusion des rayons X aux petits angles (SAXS), la microscopie électronique en transmission (MET) et la cryo-microscopie électronique en transmission (cryo-TEM).Les propriétés de diffusion optique des clusters synthétisés sont étudiées en utilisant une configuration de diffusion statique de la lumière (SLS) résolue en polarisation et à angle variable. Les données mesurées sont analysées et comparées à des calculs théoriques et des simulations. L'influence de la taille R et de la fraction volumique f des clusters sur leurs propriétés de diffusion est mise en évidence expérimentalement. La présence de multipôles électriques et magnétiques et leurs contributions aux propriétés de diffusion des agrégats sont démontrées expérimentalement. Les résultats expérimentaux sont en bon accord avec les simulations qui indiquent que les amas de rayon R = 120 nm et de fraction volumique f supérieure à 0,3 présentent des propriétés de diffusion directionnelle exceptionnelles telles que celles attendues pour des diffuseurs de Huygens utilisés pour la fabrication de métasurfacesThis thesis is dedicated to finding a new route towards the realization of optical metasurfaces using “bottom-up” approaches based on wet chemistry and self-assembly.In this project, we use an emulsion-based formulation route to synthesize clusters of gold nanoparticles. The formulation route involves emulsifying a suspension of gold nanoparticles in water into an oil phase using adapted surfactants. This step is followed by the controlled evaporation of the water from the droplets under low pressure to confine the nanoparticles in the final clusters. The surface of the gold nanoparticles were previously functionalized in order to retain their surface plasmon resonance properties in the final assembly. The structure of the clusters, precisely their internal gold volume fraction f, is controlled by varying the molar mass and surface density of the grafting polymer. The final structure of the clusters isstudied using small angle x-ray scattering (SAXS), transmission electron microscopy (TEM) and cryogenic transmission electron microscopy (cryo-TEM).The optical scattering properties of the synthesized clusters are studied using a variable angle polarization resolved static light scattering (SLS) setup. The data measured using this setup are analyzed and also compared to theoretical calculations and simulations. The influence of the size R and the volume fraction f of the clusters on their scattering properties is experimentally evidenced using the SLS setup. The presence of electric and magnetic multipoles and their contributions to the scattering properties are experimentally demonstrated. The experimental results are in good agreement with the simulations which indicate that clusters with radius R = 120 nm and volume fraction f higher than 0.3 exhibit exceptional directional scattering properties as expected for Huygens scatterers used for the fabrication of metasurfaces
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Li, Duanhui. „Micro optics for micro hybrid concentrator photovoltaics“. Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/123563.
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This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2019
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 113-124).
Concentrating photovoltaics (CPV) systems use concentrating optical elements to significantly reduce the material and processing costs of multi-junction high efficiency solar cells and improve the conversion efficiency. However, several issues hindered the development of CPV technologies due to the fundamental limit of thermodynamics and practical difficulties of manufacturing and deployment, such as system bulkiness, tight tracking error, thermal management and inability to collect diffuse irradiance. By dramatically scaling down the dimensions of the cells to the level of hundreds of microns and accordingly the concentrating optics, micro hybrid CPV overcomes the listed issues and also delivers a small form factor module prole similar to conventional at panel PV. In this thesis, we are focusing on the critical optical components in the micro hybrid CPV: the micro optics. First, we demonstrated a wafel-level micro hybrid CPV module based on Si fabrication.
By introducing the micro cavities in Si wafer with wet etching, this novel micro optical element illustrates its potential for cost-eective collection of both direct and diffuse sunlight, thereby extending the geographic and market domains for cost-eective PV system deployment. By improving the CPV figure of merit by 46%, our micro hybrid CPV module demonstrated state-of-the-art small-form-factor CPV module optical performance. Next, we focused on developing a micro-prism-array based low-prole spectrum splitting optics assembly. By novelly combining conjugate optics design with materials optical properties, the high-efficiency, low-cost, and low-prole optics potentially enables significant improvement on solar module performance and reduction of energy production costs. Lastly, we developed a simulation frame work to generate annualized diffuse radiance energy distribution map that covers the whole United States region.
This simulation approach accounts for different geographic locations and weather conditions and aims to provide high accuracy reference for diffuse concentrator design.
by Duanhui Li.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Materials Science and Engineering
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Dibos, Alan. „Nanofabrication of Hybrid Optoelectronic Devices“. Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:17463975.
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The material requirements for optoelectronic devices can vary dramatically depending on the application. Often disparate material systems need to be combined to allow for full device functionality. At the nanometer scale, this can often be challenging because of the inherent chemical and structural incompatibilities of nanofabrication. This dissertation concerns the integration of seemingly dissimilar materials into hybrid optoelectronic devices for photovoltaic, plasmonic, and photonic applications. First, we show that combining a single strip of conjugated polymer and inorganic nanowire can yield a nanoscale solar cell, and modeling of optical absorption and exciton diffusion in this device can provide insight into the efficiency of charge separation. Second, we use an on-chip nanowire light emitting diode to pump a colloidal quantum dot coupled to a silver waveguide. The resulting device is an electro-optic single plasmon source. Finally, we transfer diamond waveguides onto near-field avalanche photodiodes fabricated from GaAs. Embedded in the diamond waveguides are nitrogen vacancy color centers, and the mapping of emission from these single-photon sources is demonstrated using our on-chip detectors, eliminating the need for external photodetectors on an optical table. These studies show the promise of hybrid optoelectronic devices at the nanoscale with applications in alternative energy, optical communication, and quantum optics.Engineering and Applied Sciences - Applied Physics
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Diaz, Fernando Javier. „On Hybrid Plasmonic Waveguides for Integrated Nonlinear Optics“. Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/20282.
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The promise of plasmonics to compress light into sub-wavelength regions holds a potential pathway for nanoscale nonlinear optical devices. However an inherent trade-o? between light con?nement and propagation loss presently limits its use. A new type of plasmonic structure, which combines the best attributes of dielectric and plasmonic waveguides, has been proposed. Recent theoretical studies of these hybrid plasmonic waveguides, along with some experimental results, indicate that these structures can maintain a high ?eld con?nement while reducing propagation loss to moderate levels. Hence, this new structure obtains the best of both platforms and may be key to producing e?cient all optical nonlinear devices. If compact optical data processing is to be achieved via hybrid plasmonic structures, it is necessary to investigate their nonlinear properties and compare them to alternative platforms. Although simulations and theoretical work on hybrid modes for a large range of geometries and structures have been publish, there has been little experimental work investigating its nonlinear properties.In this thesis the candidate experimentally investigates the nonlinear properties of a hybrid plasmonic structure. The proposed structure is based on a silicon nanowire, which allows the use of a bare silicon waveguide as a control sample. The structure geometry is varied slightly in order to measure its e?ect on the nonlinearity, positive results in this regards would indicate that there is room for structure optimization. In order to achieve the experimental results a sensitive method for measuring small nonlinear phase shifts was developed and employed. This method enables the candidate to measure the nonlinear phase shift produced by waveguides of tens of micrometer in length. Further theoretical investigation is carried out regarding the platforms nonlinear properties, such as the physical origin of their strong nonlinear parameter and the limits to their optimization. The work in this thesis adds to the body of knowledge regarding the nonlinear properties for hybrid plasmonic structures from both an experimental and theoretical stand point.
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Buller, Steven Harris. „PHOTOREFRACTIVE THIN FILMS AND POLYMERS FOR USE IN ORGANIC-INORGANIC HYBRID CELLS“. Wright State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=wright1333207525.
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Lu, Dong. „Hybrid organic-inorganic sol-gel materials and components for integrated optoelectronics“. Diss., The University of Arizona, 2004. http://hdl.handle.net/10150/280624.
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On the technical platform of hybrid organic-inorganic sol-gel, the integrated optoelectronics in the forms of heterogeneous integration between the hybrid sol-gel waveguide and the high refractive index semiconductors and the nonlinear functional doping of disperse red chromophore into hybrid sol-gel is developed. The structure of hybrid sol-gel waveguide on high index semiconductor substrate is designed with BPM-CAD software. A hybrid sol-gel based on MAPTMS and TEOS suitable for lower cladding for the waveguide is developed. The multi-layer hybrid sol-gel waveguide with good mode confinement and low polarization dependence is fabricated on Si and InP. As proof of concept, a 1 x 12 beam splitter based on multimode interference is fabricated on silicon substrate. The device shows excess loss below 0.65 dB and imbalance below 0.28 dB for both TE and TM polarization. A nonlinear active hybrid sol-gel doped with disperse red 13 has been developed by simple co-solvent method. It permits high loading concentration and has low optical loss at 1550 nm. The second-order nonlinear property of the active sol-gel is induced with corona poling and studied with second harmonic generation. A 3-fold of enhancement in the poling efficiency is achieved by blue light assisted corona poling. The chromophore alignment stability is improved by reducing the free volume of the formed inorganic network from the sol-gel condensation reaction. An active sol-gel channel waveguide has been fabricated using active and passive hybrid sol-gel materials by only photopatterning and spin-coating. An amplitude modulator based on the active sol-gel containing 30 wt.% of DR13 shows an electro-optic coefficient of 14 pm/V at 1550 nm and stable operation within the observation time of 24 days.
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Schalch, Jacob. „Hybrid Terahertz Metamaterials| From Perfect Absorption to Superconducting Plasmonics“. Thesis, University of California, San Diego, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10980156.
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Metamaterials operating at terahertz (THz) region of the electromagnetic spectrum have remained have remained a promising area of study not only for realizing technologies in a historically underdeveloped spectral regime, but also as a scientific tool for exploring and controlling fundamental physical phenomena at meV energy scales in a variety of condensed matter systems. In this thesis, I will present several projects in which metamaterials and more traditional condensed matter systems are integrated into hybrid metamaterial systems. We leverage these systems to realize new practical THz devices, as well as to couple to and control quantum phenomena in condensed matter systems. I will begin with an introduction to the conceptual, numerical, and experimental techniques in the THz metamaterial toolbox. The first research endeavor I will discuss is a metamaterial system that incorporates perhaps the simplest material; air. This metamaterial perfect absorber with a continuously tunable air dielectric layer allows for comprehensive exploration of metamaterial absorber systems, and demonstrates some unique phenomena owing to its lossless dielectric layer. Next I will introduce an applications oriented device; an electrically actuated broadband terahertz switch which transitions from a non-reflective, transmissive state to a fully absorptive state. It employs an all dielectric metamaterial layer to suppress reflections and trap light, and an electrically actuated phase change material, VO 2 to transition between states. The final section of this dissertation will explore strong coupling effects between a metamaterial and the superconducting c-axis Josephson plasmon in the layered cuprate, La2–x SrxCuO4. Preliminary measurements are first presented then followed by high field THz measurements in which complex nonlinear behavior is observed.
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West, Lamar. „Analysis and simulation of reverse path laser clipping in subcarrier multiplexed hybrid fiber coax networks“. Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/13301.
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Mishechkin, Oleg. „Integrated optical components using hybrid organic-inorganic materials prepared by sol-gel technology“. Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/280437.
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A technological platform based on low-temperature hybrid sol-gel method for fabrication of optical waveguides and integrated optical components has been developed. The developed chemistry for doping incorporation in the host network provides a range of refractive indexes (1.444-1.51) critical for device optimization. A passivation method for improving long-term stability of organic-inorganic sol-gel material is reported. The degradation of waveguide loss over time due to moisture adsorption from the atmosphere is drastically suppressed by coating the material with a protective thin SiO2 film. The results indicate a long-term optical loss below 0.3 dB/cm for protected waveguides. The theory of multimode interference couplers employing self-imaging effect is described. A novel approach for design of high-performance MMI devices in low-contrast material is proposed. The design method is based on optimization of refractive index contrast and width of a multimode waveguide (the body of MMI couplers) to achieve a maximum number of constructively interfering modes resulting to the best self-imaging. This optimization is carried out using 3D BPM simulations. This method was applied to design 1 x 4, 1 x 12, and 4 x 4 MMI couplers and led to a superior performance in excess loss, power imbalance in output ports, and polarization sensitivity. Taking advantage of the inherent input-output phase relations in a 4 x 4 MMI coupler, an optical 90° hybrid is realized by incorporation a Y-junction to coherently excite two ports of the coupler. A series of MMI couplers were fabricated and characterized. The experimental results are in good agreement with the design. Measured performance of the sol-gel derived MMI components was compared to analogues fabricated by other technologies. The comparison demonstrates the superior performance of the sol-gel devices. The polarization sensitivity of all fabricated couplers is below 0.05 dB.
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Alcaraz, Iranzo David. „Study of graphene hybrid heterostructures for linear and nonlinear optics“. Doctoral thesis, Universitat Politècnica de Catalunya, 2020. http://hdl.handle.net/10803/669309.
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Graphene is the first of the 2D-material family. It is formed by carbon atoms arranged in a honeycomb lattice, which confers it intriguing physical properties that are still being discovered nowadays. A fundamental advantage found in graphene is the ability to gate tune “in-situ“ its optical response from reflective (metallic) to absorptive (lossy dielectric). It is in the reflective conditions when it becomes more interesting since it supports surface plasmon polaritons in the mid-infrared, similar to metals in the near-infrared and visible spectral regions. Surface plasmons in metals are known to be more confined than free space propagating light. But graphene naturally excels in this aspect by offering a confinement factor around 100, which causes light to couple in inefficiently.
Several studies on metal plasmonics have shown the possibilities of confining light into tiny spatial dimensions with applications in molecular sensing as an example. Often, metal plasmons are used in the visible and IR regions with moderate confinement. However, Landau damping limits the optical field confinement due to penetration in the material and the consequent losses. In this thesis, it is shown that graphene-insulator-metal hybrid heterostructures can overcome that limitation by efficiently exciting plasmons in unpatterned graphene with vertical confinement down to the ultimate one-atom insulator thickness. It is accomplished by encapsulating graphene with a single layer of h-BN (or thicker oxide layers for the systematic study) and fabricating metallic nano/micro-ribbons on top. The transmission extinction of the samples was measured and compared with theoretical models accounting for material nonlocal permittivity. The ultimate confinement and the validity of the excitation method are confirmed enabling a path towards ultrastrong light-matter interaction.
An example application of the aforementioned method to graphene nonlinear optics is also presented. The large intrinsic graphene third-order nonlinear optical response has been of great interest and it has been studied both theoretically and experimentally. However, there were not experiments covering all the expected features from the theory in the mid-infrared.
This thesis expands the measurement range to cover the mentioned gap in planar graphene. Additionally, field enhancement and confinement provided by the hybrid heterostructure was exploited to increase the nonlinear third-harmonic generation signal in more than three orders of magnitude. Intriguingly, it was found that some structures presented further modulation of the nonlinear signal which is attributed to the oscillatory nature of graphene plasmons. This opened an extra channel for extreme nonlinear gate tunability for the optimized parameters.
To summarize, this thesis presented means to achieve the regime of ultrastrong light-matter interaction, it fully characterizes it down to the one-atom spacer limit, and provides an example while demonstrating its applicability in graphene nonlinear optics.El grafeno es el primero de la creciente familia de materiales 2D. Está formado por átomos de carbono dispuestos en una red de panal que le confiere propiedades físicas intrigantes que todavía se están descubriendo hoy en día. Una ventaja fundamental que encontramos en el grafeno es la capacidad de modificar ¿in-situ¿ su respuesta óptica de reflectante (metálico) a absorbente (dieléctrico). Es en el primero cuando el grafeno se muestra más interesante, ya que admite plasmones superficiales en el infrarrojo medio, similarlmente a los metales en las regiones espectrales del infrarrojo cercano y el visible. Se sabe que los plasmones superficiales en metales están más confinados que la luz que se propaga libremente. El grafeno sobresale en este aspecto al ofrecer un factor de confinamiento alrededor de 100 de forma natural, con la contrapartida de que la luz se acople de manera muy ineficiente a los plasmones en grafeno. Varios estudios sobre plasmones metálicos han demostrado que las posibilidades de confinar la luz en pequeñas dimensiones espaciales pueden ser aplicadas, por ejemplo, en la detección de biomoléculas. A menudo, los plasmones metálicos se usan en las regiones visibles e IR con un confinamiento moderado. Sin embargo, el amortiguamiento de Landau limita dicho confinamiento del campo electromagnético debido a la penetración de éste en el material y las consiguientes pérdidas. En esta tesis, se muestra que las heteroestructuras híbridas de grafeno-dieléctrico-metal pueden superar esa limitación excitando eficientemente los plasmones en grafeno extendido con confinamiento vertical máximo, hasta el espesor de un solo átomo de material dieléctrico. Tal efecto se logra encapsulando el grafeno con una sola capa de h-BN y fabricando nano/microtiras metálicas sobre éstos. Otros espesores y materiales también fueron estudiados. La extinción en transmisión de las muestras se midió y comparó con modelos teóricos que incluyen la permitividad no local (dependiente también del momento) de los materiales. El confinamiento final y la validez del método de excitación se confirman, permitiendo así allanar el camino hacia la interacción ultra-fuerte de luz y materia. También se presenta un ejemplo de aplicación de este método al campo de la óptica no lineal con grafeno. La gran respuesta óptica no lineal intrínseca de tercer orden del grafeno ha sido de gran interés y se había estudiado tanto teórica como experimentalmente en la comunidad. A pesar de ello, no hubo experimentos que cubrieran todas las características esperadas de la teoría en el infrarrojo medio por falta de rango en el dopaje del material. Esta tesis amplía dicho rango de medición para cubrir la brecha mencionada en grafeno extendido. Además, la mejora en el confinamiento y el aumento de la densidad de campo electromagnético proporcionados por la heteroestructura híbrida se explotaron para aumentar la generación de señal no lineal del tercer armónico en hasta más de tres órdenes de magnitud. Curiosamente, se encontró que algunas estructuras presentaban una modulación adicional de la señal no lineal que se atribuye a la naturaleza oscilatoria (en el espacio) de los plasmones de grafeno y su resonancia en la estructura. Esto permite la futura exploración de un canal basado en la alta modulación de señal no lineal mediante el voltaje de puerta optimizando los dispositivos para esta finalidad. En resumen, esta tesis presenta un medio para alcanzar el régimen de interacción ultrafuerte entre luz y materia, lo caracteriza completamente hasta el límite inferior de usar un espaciador de un solo átomo de espesor. Asimismo, proporciona un ejemplo mientras demuestra su aplicabilidad en la óptica no lineal con grafeno.
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Albrecht, Gelon [Verfasser], und Harald [Akademischer Betreuer] Giessen. „Hybrid materials for nonlinear optics / Gelon Albrecht ; Betreuer: Harald Giessen“. Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2018. http://d-nb.info/1154434958/34.
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Callahan, John J. „Optoelectronic hybrid integration utilizing Au/Sn bonding“. Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/15461.
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Scott, G. „Optogalvanic frequency stabilization of hybrid TEA-COsub(2) lasers“. Thesis, University of Strathclyde, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372097.
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Djeghelian, Hagop. „Synthesis of fluoroaryl functionalized organic-inorganic hybrid glasses for integrated optics“. Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40835.
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Fluorinated organic-inorganic hybrid polymers have attracted interest over the last decade for their potential in guided wave optics. Some examples include tunable optical filters, switches, splitters, directional couplers, and modulators. Our study focuses on the synthesis and polymerization of a series of alkoxysilane monomers derivatized with different fluorinated functionalities. These monomers were prepared with a view to have a well defined refractive index, optical transparency, optical loss, mechanical flexibility, thermal stability and ease of processing. Hydrolysis and condensation experiments are performed on these monomers with different H2O:Si molar ratios to monitor the formation of siloxane backbones from fluoroaryl functionalized alkoxysilanes through the sol-gel process. These results are examined by NMR spectroscopy. A non-hydrolytic route to organically modified low-OH Ti/Si hybrid polymers is also studied. These polymers are synthesized by the use of boric acid for hydrolysis and titanium ethoxide, along with fluoroaryl functionalized alkoxysilane precursors for condensation. Homogenous films are made from the sol phase fluids and photolithographic experiments are conducted to fabricate waveguides.Durant la dernière décennie, les matériaux polymères hybrides organique-inorganiques fluorés ont attiré une attention considérable en raison de leurs potentiels comme guides d’ondes optiques. Certains exemples ont demontré leurs efficacités en tant que filtres optiques accordables, commutateurs, doubleurs, coupleurs directionnels, et modulateurs. Notre étude s’est concentrée sur la synthèse et la polymérisation d’une série de monomères d’alkoxysilane fonctionnalisés par différents groupements fluorés. Ces monomères ont été préparés en vue d’obtenir des caractères bien définis tel que l’indice de réfraction, la transparence optique, la perte optique, la flexibilité mécanique, la stabilité thermique et la simplicité de préparation. L’hydrolyse et la condensation de ces monomères ont été menées en présence de différents ratios molaires de H2O:Si afin de suivre la formation des enchaînements siloxanes à partir d’alkoxysilanes fonctionnalisés par des groupements aromatiques fluorés via le procédé sol-gel. Ces résultats ont été examinés par spectroscopie RMN. Une voie non-hydrolytique pour la synthèse de matériaux polymères Ti/Si hybrides, modifiés organiquement et à fonctionalité–OH réduite, a été également étudiée. Ces polymères ont été synthétisés grâce à l’hydolyse en présence d'acide borique et condensation en présence d’éthoxide de titane, avec des précurseurs d’alkoxysilane fonctionnalisés par des groupements aromatiques fluorés. Des films homogènes ont été préparés de ces fluides sol phase et des études photolithographiques ont été conduites pour la fabrication de guides d’ondes.
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Abadi, Mojtaba. „A hybrid free space optics/radio frequency antenna : design and evaluation“. Thesis, Northumbria University, 2017. http://nrl.northumbria.ac.uk/36012/.
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Free space optical (FSO) communication provides high speed data communications with high flexibility and cost-effectiveness. However, FSO links are sensitive to atmospheric effects such as fog, smoke and turbulence. To address the problem, this research is investigating a hybrid FSO and RF technology to ensure link availability under all weather conditions as part of the last mile access networks. The research exclusively investigates design, implementation, and assessment of a novel dual purpose hybrid FSO/RF antenna. The technical issues are interference between FSO and RF parts; compactness of the design; quality of service; and robustness. As part of the design a conventional RF antenna scheme, known as Cassegrain antenna is adopted, and a new design scheme for a hybrid antenna is proposed. For the FSO part an optical transceiver aperture, which is composed of optical lenses and optical fibres, is designed and incorporated in the shadowing region of the sub-reflector of Cassegrain antenna. The use of lens and fibre ensures the isolation between the optical and RF parts. Based on the initial design, modifications are made to enhance the hybrid antenna performance. In this work the focus of the research is on the optical part and how it is incorporated as part of the RF antenna. As part of the optical design, spatial diversity and differential signalling techniques are adopted. Majority-logic combining is adopted from RF technology and the performances of a FSO system implementing combining methods are compared for various turbulent regimes. The concept of differential signalling is investigated in terms of the channels correlation and it is shown that the variation of the detection threshold level reduces in correlated channels. A new design method is given based on spatial diversity and differential signalling techniques. To simulate the RF part, CST STUDIO SUITE® software is used, whereas Monte-Carlo simulation is used for performance estimation of the FSO link. Also provided are the detailed mathematical modelling of the hybrid FSO/RF system. The proposed hybrid antenna is fabricated and evaluated and results are compared with simulation and predicted data. Based on the recorded data of a real hybrid FSO/RF channel the performance of hybrid FSO/RF link employing the hybrid antenna with a switching mechanism is evaluated. Through this thesis, the detailed guidelines on design of the hybrid antenna are outlined and when necessary, the significant issues are discussed and addressed. Since the propose of this PhD is to outline and demonstrate the proof of concept for the proposed hybrid antenna, therefore the focus has been on the design, evaluation and the minimum performance requirements rather than the best possible performance or optimising the communication link quality. The outcome of the thesis will be a prototype antenna with a gain of 29.2 dBi and efficiency of 59 % at the frequency of 10 GHz for use in a hybrid FSO/RF system. It will be shown that the designed antenna is able to provide a hybrid link with 99.8 % availability and 1 Gbits/sec data rate at the recorded fog and rain channel conditions.
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Jewell, Sharon Ann. „Optical waveguide characterisation of hybrid aligned nematic liquid crystal cells“. Thesis, University of Exeter, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269682.
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Sung, Jin Won. „A NEW HYBRID DIFFRACTIVE PHOTO-MASK TECHNOLOGY“. Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2391.
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In the field of photolithography for micro-chip manufacturing, the photo-mask is used to print desired patterns on a proper photo-resist on wafer. The most common type of photo-mask is binary amplitude mask made an opaque layer of chrome. The principle and potential application of hybrid photo-mask with diffractive phase element and binary amplitude is presented in this dissertation paper from both numerical modeling and experimental research. The first important application is the characterization of aberration in the stepper system using hybrid diffractive photo-mask. By utilizing multiple diffractive illumination conditions, it is possible to characterize Zernike wave front aberration coefficients up to any desired order. And, the second application is the use of binary phase grating mask for analog micro-optics fabrication. This approach of using binary phase grating mask for fabricating analog micro-optics turned out to be a very effective alternative for gray-scale mask technology. Since this is a pure phase only mask, it doesn't cause any scattered noise light like half-tone mask and it results in smooth desired resist profile. The benefits and limitations of hybrid diffractive photo-mask approach for both applications are discussed.Ph.D.
Other
Optics and Photonics
Optics
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Gullans, Michael John. „Controlling Atomic, Solid-State and Hybrid Systems for Quantum Information Processing“. Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:11146.
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Quantum information science involves the use of precise control over quantum systems to explore new technologies. However, as quantum systems are scaled up they require an ever deeper understanding of many-body physics to achieve the required degree of control. Current experiments are entering a regime which requires active control of a mesoscopic number of coupled quantum systems or quantum bits (qubits). This thesis describes several approaches to this goal and shows how mesoscopic quantum systems can be controlled and utilized for quantum information tasks.Physics
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Farzam, Parisa. „Hybrid diffuse optics for monitoring of tissue hemodynamics with applications in oncology“. Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/283982.
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Noninvasive measurement of hemodynamics at the microvascular level may have a great impact on oncology in clinics for diagnosis, therapy planning and monitoring, and, in preclinical studies. To this end, diffuse optics is a strong candidate for noninvasive, repeated, deep tissue monitoring.
In this multi-disciplinary, translational work, I have constructed and deployed hybrid devices which are the combination of two qualitatively different methods, near infrared diffuse optical spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS), for simultaneous measurement of microvascular total hemoglobin concentration, blood oxygen saturation and blood flow.
In a preclinical study, I applied the hybrid device to monitor the response of renal cell carcinoma in mice to antiangiogenic therapy. The results suggest that we can predict the output of therapy from early hemodynamic changes, which provide us with valuable information for better understanding of the tumor resistance mechanism to antiangiogenic therapies.
In two in vivo studies in human volunteers, I have developed protocols and probes to demonstrate the feasibility of noninvasive diffuse optical spectroscopy to investigate the pathophysiology of bone. First study was study on the physiology of the patella microvasculature, the other introduced the manubrium as a site that is rich in red bone mar- row and accessible to diffuse optics as a potential window to monitor the progression of hematological malignancies.
Overall, during my Ph.D., I have developed instrumentation, algorithms and protocols and, then, applied this technique for preclinical and clinical investigations. My research is a link between preclinical and clinical studies and it opens new areas of applications in oncology.La medición no invasiva de la hemodinámica a nivel microvascular puede alcanzar un gran impacto en oncología: en las clínicas para el diagnóstico, la planeación y monitorización de las terapias, y en estudios preclínicos. La óptica difusa es una fuerte candidata para la monitorización no invasiva y repetida del tejido profundo. En este trabajo multidisciplinario y traslacional, construí e implementé dispositivos híbridos que son la combinación de dos métodos cualitativamente diferentes: espectroscopía infrarroja de óptica difusa -near infrared diffuse optical spectroscopy (NIRS)- y espectroscopía de correlación de luz difusa -diffuse correlation spectroscopy (DCS)-. Estos híbridos permiten la medición simultánea de la concentración de hemoglobina total en sangre, la saturación de oxígeno y el flujo sanguíneo. En un estudio preclínico, apliqué el dispositivo híbrido para monitorizar la respuesta de carcinomas de células renales, implantados en ratones, a terapias antiangiogénicas. Los resultados sugieren que podemos predecir la evolución de la terapia con base en cambios hemodinámicos tempranos, lo cual proporciona información valiosa para un mejor entendimiento del mecanismo de resistencia de los tumores a las terapias antiangiogénicas. En dos estudios in vivo realizados en pacientes voluntarios, desarrollé protocolos y sondas para demostrar la viabilidad de la espectroscopía de óptica difusa no invasiva en el estudio de la patofisiología ósea. El primer estudio se concentró en la fisiología microvascular de la rótula y en el otro se muestra que el manubrio, hueso rico en médula ósea roja, es un sitio accesible para la óptica difusa, y se presenta como una ventana para monitorizar la progresión de enfermedades hematológicas malignas. En resumen, durante mi trabajo doctoral, desarrollé instrumentación, algoritmos y protocolos que posteriormente apliqué en estudios preclínicos y clínicos. Mi trabajo de investigación constituye así un enlace entre estos estudios y abre nuevas áreas de aplicación en oncología.
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Gurney, James A. „Hybrid sol-gel glasses for nonlinear optics/artificial films from cellular automata“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0006/MQ44177.pdf.
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Bettahar, Houari. „High accurate 3-D photo-robotic nano-positioning for hybrid integrated optics“. Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCD019/document.
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L'intégration hybride d'éléments photoniques individuels offre la promesse de fournir des performances très élevées, de proposer de nouvelles fonctionnalités et produits optiques mais aussi pour exploiter de nouveaux modes de propagation des faisceaux lumineux. Cette approche repose sur la capacité d'un positionnement multi Degré-De-Liberté (DDL) précis des éléments photoniques individuels. Ainsi, la mesure multi-DDL imprécise et le contrôle inexact des robots sont les principaux verrous à surmonter, notamment à l'échelle micrométrique Pour cela, une approche photo-robotique originale a été proposée, s'appuyant sur les mouvements d'un robot à plusieurs DDL associé à l'utilisation de l'interférométrie Fabry-Perot 1-D pour réaliser une mesure de pose multi-DOF. Cette approche intègre notamment la question de l'étalonnage des robots 6-DDL qui a été étudiée à travers l'étalonnage des paramètres géométriques extrinsèques et/ou intrinsèques. Afin de trouver la stratégie d'étalonnage appropriée pour une grande précision de positionnement et adaptée au contexte du micro-positionnement de composants optiques, une quantification et une analyse de durabilité des performances optiques et robotiques ont été étudiées. Des études expérimentales ont démontré qu'une précision de positionnement en rotation et en translation de 0.004° et 27.6 nm ont été obtenues respectivement.Cette approche photo-robotique a été notament appliquée pour réaliser le positionnement 6-DDL d'une lamelle optique par rapport à une fibre optique avec une grande précision ce qui conduit également à des performances optiques maximales. L'approche a également été appliquée pour contrôler les états de polarisation à la sortie d'un système optique hybride en réalisant des rotations très précises d'une lamelle d'onde optique spécifique autour de son axe optique. Les résultats expérimentaux démontrent notamment que la grande précision du positionnement permet un contrôle précis de l'état de polarisation optiqueThe hybrid integration of individual photonic elements appears as promising, because it may provide high performances, propose new optical functionalities and products and exploit new propagation modes of light beams. This approach requires an accurate multi Degree-Of-Freedom (DOF) positioning of the individual photonic elements. Hence, the inaccurate multi-DOF measurement and robots control are the main locks to overcome, notably at the micro-scale. For this sake, an original photo-robotic approach has been proposed, relying on multi-DOF robot motion associated with the use of 1-D Fabry-Perot interferometry measure to realize multi-DOF pose measure. This approach notably integrates the issue of 6-DOF robot calibration that has been studied through extrinsic and/or intrinsic geometric parameters calibration. In order to find the appropriate calibration strategy for high positioning accuracy and adapted to the context of micro-positioning of optical components, a quantification and durability analysis of optical and robotic performances have been investigated. Experimental investigations demonstrate that a rotational and translational positioning accuracy of 0.004° and 27.6 nm have been obtained respectively.This photo-robotic approach has especially been applied to achieve the 6-DOF positioning of an optical lamella relative to an optical fiber with high accuracy that also conduct to maximum optical performances. The approach has also been applied to control the optical polarization states at the output of an hybrid optical system through achieving high accurate rotations of a specific optical wave plate around the optical axis. The experimental results notably demonstrate that the high positioning accuracy enables to accurately control of the optical polarization state
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Le, Jeannic Hanna. „Optical Hybrid Quantum Information processing“. Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066596/document.
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Approche hybride du traitement quantique de l'information La dualité onde-particule a conduit à deux façons d'encoder l'information quantique, les approches continues et discrètes. L'approche hybride a récemment émergé, et consiste à utiliser les concepts et boites à outils des deux approches, afin de venir à bout des limitations intrinsèques à chaque champ. Dans ce travail de thèse, nous allons dans une première partie utiliser des protocoles hybrides de façon à générer des états quantiques non-gaussiens de la lumière. A l'aide d'oscillateurs paramétriques optiques, et de détecteur de photons supraconducteurs, nous pouvons générer des photons uniques extrêmement purs très efficacement, ainsi que des états chats de Schrödinger, qui permettent d'encoder l'information en variables continues. Nous montrons également en quoi des opérations de variables continues peuvent aider cette génération. La méthode utilisée, basée sur la génération " d'états-noyaux " rend en outre ces états plus robustes à la décohérence. Dans une seconde partie, dans le contexte d'un réseau hétérogène, basé sur différents encodages, relier de façon quantique les deux mondes, nécessite l'existence d'intrication hybride de la lumière. Nous introduisons la notion d'intrication hybride, entre des états continus et discrets, et nous en montrons une première application qui est la génération à distance de bit quantique continu. Nous implémentons ainsi également une plateforme polyvalente permettant la génération d'états " micro-macro " intriquésIn quantum information science and technology, two traditionally-separated ways of encoding information coexist -the continuous and the discrete approaches, resulting from the wave-particle duality of light. The first one is based on quadrature components, while the second one involves single photons. The recent optical hybrid approach aims at using both discrete and continuous concepts and toolboxes to overcome the intrinsic limitations of each field. In this PhD work, first, we use hybrid protocols in order to realize the quantum state engineering of various non-Gaussian states of light. Based on optical parametric oscillators and highly-efficient superconducting-nanowire single-photon detectors, we demonstrate the realization of a high-brightness single-photon source and the quantum state engineering of large optical Schrödinger cat states, which can be used as a continuous-variable qubit. We show how continuous-variable operations such as squeezing can help in this generation. This method based on so-called core states also enables to generate cat states that are more robust to decoherence. Second, in the context of heterogeneous networks based on both encodings, bridging the two worlds by a quantum link requires hybrid entanglement of light. We introduce optical hybrid entanglement between qubits and qutrits of continuous and discrete types, and demonstrate as a first application the remote state preparation of continuous-variable qubits. Our experiment is also a versatile platform to study squeezing-induced micro-macro entanglement
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Chamanzar, Maysamreza. „Hybrid nanoplasmonic-nanophotonic devices for on-chip biochemical sensing and spectroscopy“. Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/50145.
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Hybrid plasmonic-photonic structures were introduced as novel platforms for on-chip biochemical sensing and spectroscopy. By appropriate coupling of photonic and plasmonic modes, a hybrid architecture was realized that can benefit from the advantages of integrated photonics such as the low propagation loss, ultra-high Q modes, and robustness, as well as the advantages of nanoplasmonics such as extreme light localization, large sensitivities, and ultra-high field enhancements to bring about unique performance advantages for efficient on-chip sensing. These structures are highly sensitive and can effectively interact with the target biological and chemical molecules. It was shown that interrogation of single plasmonic nanoparticles is possible using a hybrid waveguide and microresonator-based structure, in which light is efficiently coupled from photonic structures to the integrated plasmonic structures. The design, implementation, and experimental demonstration of hybrid plasmonic-photonic structures for lab-on-chip biochemical sensing applications were discussed. The design goal was to achieve novel, robust, highly efficient, and high-throughput devices for on-chip sensing. The sensing scenarios of interest were label-free refractive index sensing and SERS. Nanofabrication processes were developed to realize the hybrid plasmonic-photonic structures. Silicon nitride was used as the material platform to realize the integrated photonic structure, and gold was used to realize plasmonic nanostructures. Special optical characterization setups were designed and implemented to test the performance of these nanoplasmonic and nanophotonic structures. The integration of the hybrid plasmonic-photonic structures with microfluidics was also optimized and demonstrated. The hybrid plasmonic-photonic-fluidic structures were used to detect different analytes at different concentrations. A complete course of research from design, fabrication, and characterization to demonstration of sensing applications was conducted to realize nanoplasmonic and integrated photonic structures. The novel structures developed in this research can open up new potentials for biochemical sensors with advanced on-chip functionalities and enhanced performances.
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Kundur, Abhinay. „Digital and Analog Signal Encryption and Decryption in Mid RF Range Using Hybrid Acousto-Optic Chaos“. University of Dayton / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1336100009.
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Efstathiou, A. „Design considerations for a hybrid swing-arm profilometer to measure large aspheric optics“. Thesis, University College London (University of London), 2007. http://discovery.ucl.ac.uk/1444702/.
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This thesis presents issues regarding the design and implementation of a profilometer based on the swivelling motion of a pivot arm. The main advantage of such a method, over conventional profiling techniques, is that it can be easily adapted to measure a range of optics including both spherics and aspherics, convex and concave as well as a variety of optic diameters and radii of curvature. The initiative for the development of the new aspheric metrology technique comes from the need for fabrication and measurement of hundreds of aspheric segments to enable the future Extremely Large Telescopes (ELTs). A detailed investigation of currently available aspheric metrology techniques concluded with the proposal of a novel SAP with a hybrid opto-mechanical sensor as a way to tackle issues of ELT segment metrology that remain in doubt. The successful submission of the proposal to the Department of Trade and Industry resulted in the allocation of funding for the development of a functional full scale prototype. Initially a basic error model was constructed in order to forecast the error of a generic SAP and to estimate allowed sub-component tolerances. Subsequently a first, scaled- down model of an SAP was used as a test platform which guided the construction of a full-scale prototype. The prototype is capable of measuring optics up to 1 m in diameter with a minimum radius of curvature of 1.75 m for concave and 1.25 m for convex surfaces. The SAP performance was evaluated through the measurement of a 680 mm diameter optic and measurements of surface profiles with accuracy better than 20 nm were realised. The thesis describes in detail the design process followed from the conceptual idea to the implementation and evaluation of the instrument.
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McCutcheon, Robert A. „Hybrid Optomechanics and the Dynamical Casimir Effect“. Miami University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=miami1501191323617929.
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Mazzoncini, Francesco. „Multimode Quantum Communications and Hybrid Cryptography“. Electronic Thesis or Diss., Institut polytechnique de Paris, 2024. http://www.theses.fr/2024IPPAT018.
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La cryptographie quantique a été largement définie comme une forme novatrice de cryptographie ne reposant sur aucune hypothèse de difficulté computationnelle. Cependant, avec l'évolution du domaine, et en particulier alors que la distribution quantique de clé (QKD) atteint des niveaux élevés de préparation technologique, il semble qu'il faille trouver un équilibre critique. D'une part, il y a la quête du niveau de sécurité théorique le plus élevé. D'autre part, une seconde direction consiste à optimiser la sécurité et la performance pour une utilisation réelle, tout en offrant un avantage par rapport à la cryptographie classique. Dans cette thèse, nous avons exploré de nouvelles voies vers cette seconde direction, à savoir la cryptographie quantique en conditions réelles.Dans le premier projet, nous défendons un message simple mais puissant : les attaques les plus dangereuses contre la QKD, pour lesquelles le développement de contre-mesures est crucial, sont les plus faciles à mettre en œuvre. Par conséquent, nous effectuons une évaluation de la vulnérabilité d'un dispositif de QKD à variables continues, proposant une nouvelle méthodologie pour la certification de sécurité basée sur le classement des attaques.Dans le deuxième projet, nous introduisons une construction explicite pour un protocole de distribution de clés dans le modèle de sécurité Quantum Computational Timelock (QCT), où l'on suppose que le chiffrement sécurisé computationnellement ne peut être rompu qu'après un temps bien plus long que le temps de cohérence des mémoires quantiques disponibles. En tirant parti des hypothèses QCT, nous construisons un protocole de distribution de clés basé sur le problème de Hidden Matching, pour lequel il existe un écart exponentiel en complexité de communication unidirectionnelle entre les stratégies classiques et quantiques. En particulier, en exploitant cet écart exponentiel, nous débloquons la possibilité d'envoyer plusieurs copies du même état pour réaliser un établissement de clé sécurisé à long terme avec des performances qui vont au-delà de la QKD standard.En nous appuyant sur notre travail théorique sur l'établissement de clés, dont la sécurité et l'efficacité reposent sur la capacité des deux parties à résoudre un problème de complexité de communication quantique plus efficacement que ce qui est possible classiquement, dans le dernier projet expérimental, nous étudions la faisabilité de démontrer un avantage quantique en complexité de communication. En particulier, nous exploitons le mélange de modes complexe inhérent aux fibres multimodes en employant des techniques de wavefront shaping pour aborder les problèmes de complexité de communication quantiqueQuantum cryptography has been largely defined as a novel form of cryptography that would not rely on any computational hardness assumption. However, as the field progresses, and in particular as Quantum Key Distribution (QKD) reaches high technological readiness levels, it appears that there might be a critical balance to strike. On the one hand, we have the quest for the highest theoretical security level. On the other, a second direction consists in optimizing security and performance for real-world use, while still providing an edge over classical cryptography. In this thesis, we have explored new paths towards this second direction, namely real-world quantum cryptography.In the first project, we promote a simple yet powerful message: the most dangerous attacks against QKD, for which the development of countermeasures is crucial, are the easiest ones to implement. Hence, we perform a vulnerability assessment of a Continuous-Variable QKD system device, proposing a novel methodology for security certification based on attack rating.In the second project, we introduce an explicit construction for a key distribution protocol in the Quantum Computational Timelock (QCT) security model, where one assumes that computationally secure encryption may only be broken after a time much longer than the coherence time of available quantum memories. Taking advantage of the QCT assumptions, we build a key distribution protocol on top of the Hidden Matching problem, for which there exists an exponential gap in one-way communication complexity between classical and quantum strategies.In particular, by exploiting this exponential gap, we unlock the possibility of sending multiple copies of the same state to perform everlasting secure key establishment with performances that go beyond standard QKD.Building on our theoretical work on key establishment, whose security and effectiveness hinge on the ability of two parties to address a quantum communication complexity problem more efficiently than is possible classically, in the last experimental project we investigate the feasibility of demonstrating a quantum advantage in communication complexity. In particular, we leverage the intricate mode mixing inherent in multimode fibers by employing wavefront shaping techniques to tackle quantum communication complexity problems
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Andrasik, Stephen James. „NEW ORGANIC/INORGANIC HYBRID SOL-GEL NANOCOMPOSITE MATERIALS FOR RAMAN GAIN IN FIBER OPTICS“. Master's thesis, University of Central Florida, 2004. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4457.
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The recent increased availability of additional wavelengths in the telecommunications window of about 1300-1600 nm has generated an interest in new optical materials and devices that can operate outside the normally used regions of 840 nm, 1310 nm, and 1550 nm. Specifically, methods to amplify fiber optical data transmission in the regions where there is limited or no existing methods to achieve amplification is of interest in the chemistry and photonic communities. Raman gain is one method that has been proposed to passively amplify optical data transmission through a distributed process. Amplification is obtained through a nonlinear light scattering process where an optical wave is amplified at the expense of a higher frequency pump wave. Multiple wavelengths can be evenly amplified simultaneously in a desired region by specific selection of one or more pump wavelengths. Herein, the synthesis and characterization of new hybrid inorganic/organic sol-gels and monomers capable of producing broad wavelength Raman scattering over a spectral range of 1200-1670 nm are presented. The synthetic methodology developed facilitates the systematic approach to produce sol-gel derivatives with functional groups known to be strongly Raman scattering. Additionally, a method to synthesize and characterize a large number of different compounds using a combinatorial approach was demonstrated. Thio based derivatives of sulfonyldiphenol, isopropylidenediphenol, and triallyloxy triazine were synthesized in addition to thio derivatives of poly(hydroxystyrene). Micro-Raman spectra of the hybrid sol-gels, thio-based derivatives, and IR spectra of select sol-gel monomers were obtained.M.S.
Department of Chemistry
Arts and Sciences
Chemistry
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Edlund, Johan. „A parallel, iterative method of moments and physical optics hybrid solver for arbitrary surfaces“. Licentiate thesis, Uppsala universitet, Avdelningen för teknisk databehandling, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-86001.
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We have developed an MM–PO hybrid solver designed to deliver reasonable accuracy inexpensively in terms of both CPU-time and memory demands. The solver is based on an iterative block Gauss–Seidel process to avoid unnecessary storage and matrix computations, and can be used to solve the radiation and scattering problems for both disjunct and connected regions. It supports thin wires and dielectrica in the MM domain and has been implemented both as a serial and parallel solver. Numerical experiments have been performed on simple objects to demonstrate certain keyfeatures of the solver, and validate the positive and negative aspects of the MM/PO hybrid. Experiments have also been conducted on more complex objects such as a model aircraft, to demonstrate that the good results from the simpler objects are transferrable to the real life situation. The complex geometries have been used to conduct tests to investigate how well parallelised the code is, and the results are satisfactory.
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Harvey, Michael D. „Hybrid material systems for micro-optical devices : the synthesis and characterisation of dye doped mesostructured TiO2, low refractive index mesoporous SiO2 and the analysis of thin films made thereof /“. [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19323.pdf.
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Mireles, Núñez Miguel Adrián. „Hybrid diffuse optics for translational oncology and nanobiophotonics: towards a theranostic approach for emerging cancer therapies“. Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/671099.
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A pre-clinical mouse model of human clear cell renal cell carcinoma (ccRCC) was employed as a method to study the prognostic and theranostic
potential of two, non-invasive, deep tissue, diffuse optical techniques, namely broadband diffuse reflectance spectroscopy (DRS) and diffuse correlation spectroscopy (DCS). In doing so, new algorithms and methods were developed to improve the robustness and applicability
of the technology and a vision is presented for its clinical translation.
Hemodynamic biomarkers such as the total hemoglobin concentration (THC), blood oxygen saturation (SO2) and blood flow (BFI) that
were measured in a longitudinal and quantitative fashion from deep tissue layers (> 2 mm) were used to predict the outcome of an antiangiogenic
therapy, Sunitinib therapy. Hemodynamic biomarkers were shown to be useful for treatment planning prior to the onset of the therapy and, at an early stage (few days), as predictors of the therapy outcome.
The second part of this work focused on another emerging class of treatments based on the nanobiophotonics as a complementary tool
for improving other cancer therapies. The specific needs for the optimization of plasmon photo-thermal therapy based on customized
gold nanorods was studied. Based on that, it was hypothesized that the combination of DCS and DRS would enable dose planning and in vivo on-line evaluation of the treatment effects. As a means to reach this goal, this work has shown that DRS/DCS can, estimate the in vivo PEGylated gold nanorod (AuNR-PEG) concentration and detect their
accumulation and clearance from the tissues in a longitudinal manner.
Furthermore, it was shown that the injection of AuNRs-PEG do not alter the tumor hemodynamics and, that, had there been any alterations,
we could monitor its effects.
All these studies were done with a contact probe which was previously validated but was also shown to cause some systematic effects.
A proof-of-concept, scanning, non-contact system was developed and validated as a future tool to overcome these limitations.
Overall, this work contributed to bridge some of the gaps in translational oncology towards the development of personalized cancer therapies.La información hemodinámica de un modelo animal fue obtenida de manera no invasiva y longitudinal por medio de un sistema hibrido que combina las técnicas de espectroscopia de reflectancia y correlación difusa en una sonda de contacto; donde algunos de los factores que afectan la adquisición y el procesamiento de los datos fueron resueltos a través de un algoritmo desarrollado para este fin. Esta información fue obtenida en dos campos de investigación, la oncología traslacional y la nanobiofotónica. En el campo de la oncología traslacional, la información hemodinámica fue monitoreada `opticamente durante la administración de terapia antiangiogénica, permitiendo predecir desde las mediciones previas al tratamiento, la resistencia intrínseca de los tumores al tratamiento. Además, se observó que los cambios en los parámetros hemodinámicos al día tres de iniciado el tratamiento están correlacionados con el pronóstico post-terapéutico. En el campo de la nanobiofotónica, los parámetros hemodinámicos y la concentración de nanotubos de oro funcionalizados (AuNRs-PEG) fueron cuantificados simultáneamente. Se demostró que la concentración de AuNRs-PEG estimada por medio de las tecnicas de optica difusa es proporcional a la obtenida por métodos comerciales para la cuantificación ex vivo de oro en tejidos. Además, la hemodinámica se mantuvo estable aun con AuNRs-PEG circulando en la sangre, demostrando que no hay interacción entre dichos parámetros. De manera adicional, se introdujo la versión de no contacto de este sistema como un método potencial para la obtención de información hemodinámica en futuras aplicaciones. En general, este trabajo contribuye a cubrir algunas de las necesidades en los campos de la oncología traslacional y la nanobiofotónica, con vistas al desarrollo de terapias teranosticas contra el cáncer.
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Mohammadi, Fatemesadat. „Photon Emission and Lasing in Bare and Hybrid Plasmonic Semiconductor Nanowires and Nanorods“. University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin153538145368204.
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Nazo, Syanda. „A hybrid MoM/PO technique with large element PO“. Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20060.
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Thesis (MScEng)--Stellenbosch University, 2012.ENGLISH ABSTRACT: Radar Cross Section (RCS) is an important parameter in radar engineering. Often, electrically large structures are of interest in RCS analysis due to the high operating frequencies of radar systems. Simulation of these problems can be more e cient than measurement due to the cost associated with measurement. The Method of Moments/Physical Optics (MoM/PO) hybrid method combines the advantages of the MoM and PO, making it suited to solving electrically large problems that may contain some small complex detail. The requirement for high meshing resolution when analysing some electromagnetic problems, however, signi cantly increases memory requirements. As a result, the hybrid MoM/PO becomes computationally expensive for electrically large problems. In this work, a linear phase term is introduced into the RWG basis function formulation of the MoM/PO hybrid. The addition of the linear phase term allows the use of large triangular mesh elements in the PO region, resulting in the analysis of electrically large problems. The bene t of this formulation is that it allows a reduction in computational cost whilst maintaining the accuracy of the hybrid MoM/PO. This improved hybrid is tested on various planar test cases and results show that it attains the same level of accuracy as the original MoM/PO hybrid.
AFRIKAANSE OPSOMMING: Radardeursnit is 'n belangrike parameter in radaringenieurswese. As gevolg van die hoë frekwensies wat deur baie radarstelsels gebruik word, is elektriesgroot probleme dikwels van belang in die berekening van die radardeursnit van teikens. Die modellering en berekening van die radardeursnit van teikens kan meer kostedoeltre end as metings wees, as gevolg van die beduidende koste van radardeursnitmetings. Die hibriede Moment-Metode/Fisiese-Optika tegniek kombineer die voordele van die twee tegnieke, wat dit geskik maak vir elektries-groot probleme met klein, komplekse detail. Indien die gewone benadering egter gevolg word om 'n hoë resolusie faset-model te gebruik, bly dit berekeningsintensief met groot rekenaar geheuevereistes vir elektries-groot probleme. In hierdie studie word 'n lineêre fase term ingesluit in die formulering van die Rao-Wilton-Glisson (RWG) basisfunksies vorm van die hibriede Moment-Metode/Fisiese-Optika tegniek. Die toevoeging van die lineêre fase term maak dit moontlik om groot driehoekfasette in die Fisiese-Optika gebied te gebruik, wat beteken dat elektries-groot probleme makliker opgelos kan word. Die voordeel van hierdie nuwe formulering is dat die berekeningslas en -tyd verminder word terwyl die akkuraatheid van die oorspronklike hibriede Moment-Metode/Fisiese-Optika tegniek behou word. Hierdie verbeterde hibriede tegniek word getoets aan die hand van verskeie platvlak toetsgevalle en die resultate dui daarop dat die akkuraatheid vergelykbaar is met die van die oorspronklike hibriede Moment-Metode/Fisiese-Optika tegniek.
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Olson, Grant T. „Improving Hybrid Solar Cells: Overcoming Charge Extraction Issues In Bulk Mixtures of Polythiophenes and Zinc Oxide Nanostructures“. DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1257.
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Organic photovoltaics (OPVs) have received a great deal of focus in recent years as a possible alternative to expensive silicon based solar technology. Current challenges for organic photovoltaics are centered around improving their lifetimes and increasing their power conversion efficiencies. One approach to improving the lifetime of such devices has been the inclusion of inorganic metal oxide layers, but interaction between the metal oxides and common conjugated polymers is not favorable. Here we present two methods by which the interactions between polythiophenes and nanostructured ZnO can be made to be more favorable. Using the first method, direct side on attachment of polythiophene to ZnO nanowires via chemical grafting, we demonstrate chemical linkage between the polymer and ZnO phases. The attachment was confirmed to affect the morphological properties of the polymer layer as well, inducing highly ordered regions of the polymer at the ZnO surface via chemical attachment and physical adsorption. Using the second method to improve polythiophene ZnO interactions, we have functionalized ZnO nanowires with organic molecules that favorably interact with conjugated polymer and organic solvents. Photovoltaic devices were made using a blended active layer of functionalized ZnO nanowires and P3HT. Electrical analysis of the resultant devices concluded that the devices were functional photovoltaic cells and isolated the dominant loss mechanisms for further device improvement.
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Zhou, Hao. „Numerical Investigation of the Nonlinear Dynamics of a Hybrid Acousto-Optic Bragg Cell with a Variable Feedback Gain“. University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1406666390.
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Zieliński, Marcin. „Nanoscale engineering of semiconductor heterostructures for quadratic nonlinear optics and multiphoton imaging“. Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2011. http://tel.archives-ouvertes.fr/tel-00585601.
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Nonlinear coherent scattering phenomena from single nanoparticles have been recently proposed as alternative processes for fluorescence in multiphoton microscopy staining. Commonly applied nanoscale materials, however, have reached a certain limit in size dependent detection efficiency of weak nonlinear optical signals. None of the recent efforts in detection of second-harmonic generation (SHG), the lowest order nonlinear process, have been able to cross a ~40 nm size barrier for nanoparticles (NPs), thus remaining at the level of "large" nanoscatterers, even when resorting to the most sensitive detection techniques such as single-photon counting technology. As we realize now, this size limitation can be significantly lowered when replacing dielectric insulators or wide gap semiconductors by direct-gap semiconducting quantum dots (QDs). Herein, a new type of highly nonlinear nanoprobes is engineered in order to surpass above mentioned size barrier at the single nanoparticle scale. We consider two-photon resonant excitation in individual zinc-blende CdTe QDs of about 12.5 nm diameter, which provide efficient coherent SHG radiation, as high as 105 Hz, furthermore exhibiting remarkable sensitivity to spatial orientation of their octupolar crystalline lattice. Moreover, quantum confinement effects have been found to strongly contribute to the second-order nonlinear optical susceptibility χ(2) features. Quantitative characterization of the χ(2) of QDs by way of their spectral dispersion and size dependence is therefore undertaken by single particle spectroscopy and ensemble Hyper-Rayleigh Scattering (HRS) studies. We prove that under appropriate conditions, χ(2) of quantum confined semiconducting structures can significantly exceed that of bulk. Furthermore, a novel type of semiconducting hybrid rod-on-dot (RD) QDs is developed by building up on crystalline moieties of different symmetries, in order to increase their effective quadratic nonlinearity while maintaining their size close to a strong quantum confinement regime. The new complex hybrid χ(2) tensor is analyzed by interfering the susceptibilities from each component, considering different shape and point group symmetries associated to octupolar and dipolar crystalline structures. Significant SHG enhancement is consequently observed, exceeding that of mono-compound QDs, due to a coupling between two nonlinear materials and slower decoherence, which we attribute to the induced spatial charge separation upon photoexcitation.
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Donati, Gaia. „Hybrid quantum information processing with continuous and discrete variables of light fields“. Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:673338dc-1233-43c8-be93-11b748a428a9.
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Quantum correlations play a fundamental role in quantum information science. The variety of their manifestations has become increasingly apparent following the development of novel light sources, protocols and photodetectors. One broad classification identifies two instances of non-classical correlations: particle and mode entanglement. These categories mirror two coexisting descriptions of quantum systems in terms of discrete and continuous variables of the electromagnetic field. The past decades have generated a number of promising results based on schemes which encompass elements from both frameworks, rather than viewing the two descriptions as mutually exclusive. In this context, it is possible to conceive and realise experiments where either the quantum resource or the detection system is 'hybrid'. Optical weak-field homodyne detectors bring together phase sensitivity and photon counting; as such, they represent a detection scheme which works across continuous and discrete variables of the radiation field. In this thesis we present a two-mode weak-field homodyne detection layout with added photon-number resolution and apply it to the study of a split single-photon state and a squeezed vacuum state. As a first test of the capabilities of this system, we investigate the reconstruction of relevant features of a given quantum resource - such as its photon statistics - with our detection scheme. Further, we experimentally demonstrate the observation of an instance of non-classical optical coherence which combines the continuous- and discrete-variable descriptions explicitly. The ability to probe phenomena at the interface of wave and particle regimes opens the way to novel, improved schemes for quantum information processing. From a more fundamental perspective, such hybrid approaches may shed light on the very roots of quantum enhancement.
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Kedia, Sunny. „Optical Communication Using Hybrid Micro Electro Mechanical Structures (MEMS) and Commercial Corner Cube Retroreflector (CCR)“. Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5969.
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This dissertation presents a free-space, long-range, passive optical communication system that uses electrostatically modulated microelectromechanical systems (MEMS) structures coupled with a glass total internal reflection (TIR)-type corner cube retroreflector (CCR) as a non-emitting data transmitter. A CCR consists of three mirrors orthogonal to each other, so that the incident beam is reflected back to the incident beam, source. The operational concept is to have a MEMS modulator fusion with TIR CCR, such that the modulators are working periodically to disrupt the evanescent waves at the air interface of one of the three back glass faces of a TIR CCR. The MEMS chip has two primary components: (1) an array of movable light scattering silicon structures with nano roughness and (2) a glass lid with a transparent conductive indium tin oxide (ITO) film. The MEMS structures are bonded to a glass lid using flip-chip bonding. Once bonded, the MEMS structures can be modulated either toward or away from the glass lid, thus disrupting evanescent energy delivered from a probing laser beam. The MEMS structure is precisely bonded to the TIR CCR with an accuracy of 10-30 arc-seconds using a Michelson interferometry feedback system. This is a novel step by which an existing passive commercial CCR can be converted into a modulating active CCR. This CCR-MEMS unit acts as the key element of the transmitter. To illustrate the concept of a low-power, unattended, sensor-monitoring system, we developed a sensor board containing temperature, humidity, and magnetic sensors along with a microprocessor and other electronics. The sensor board and CCR board are packed together and act as the transmitter unit. We developed a benchtop system and an improved portable receiver system. The receiver system contains the laser (as source), a collimating lens (to collect retroreflected signal), an optical, narrow band pass filter, and a detector. The detector signal was amplified and filtered and sent either to the oscilloscope, a lock-in-amplifier, or a laptop to display the sensor data. Using the receiver system, a sensor-CCR-based transmitter unit, and receiver with 635 nm as source, we achieved retroreflective communication over a distance of 300 m.
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Zhou, Xuan. „Advances in hybrid plasmonics : from passive to active functions“. Thesis, Troyes, 2013. http://www.theses.fr/2013TROY0015/document.
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La plasmonique hybride est un sujet d’actualité qui exploite des interactions physiques entre nano-objets métalliques et d’autres nanomatériaux. En bénéficiant des propriétés de chacun de leurs constituants, les nanostructures hybrides sont utilisées dans de nombreuses applications comme la détection d’espèces bio-chimiques. Dans cette thèse, nous présentons une nouvelle nanostructure hybride polymère/metal qui est non seulement utilisée comme nano-émetteur anisotrope qui s’avère aussi être un outil puissant de caractérisation du champ proche optique.La fabrication de cette nouvelle nanostructure est basée sur une approche de par photopolymérisation à l’échelle nanométrique. Cette technique, en comparaison aux méthodes traditionnelles de caractérisation, ne fournit pas seulement l’image de la distribution du champ, mais permet aussi des mesures quantitatives des plasmons de surface avec une résolution sub -5nm, incluant une description fine de la décroissance exponentielle des ondes évanescentes impliquées.A l’aide du mode plasmon dipolaire, une distribution anisotrope de matériau organique est intégrée dans le voisinage de la nanoparticule métallique. Avec une haute concentration de molécules de colorant dans le polymère, l’intensité des signaux de fluorescence et Raman du nano-émetteur hybride dépend de la polarisation incidente. À notre connaissance, il s’agit de la première réalisation d’un nano-émetteur dont le milieu à gain présente une distribution spatiale complexe le rendant sensible à la polarisationHybrid plasmonics has given rise to increasing interest in the context of the interaction between metal nano-objects and other materials. By benefiting from each of its constituents, hybrid nanostructures are commonly adopted in studies and optimization of biological and chemical sensors, nanoparticle with high plasmon resonance tunability, and nano-emitters. This PhD thesis presents a hybrid nanostructure of photopolymer/metal nanoparticle that is used as a near-field characterizing tool and as an anisotropic nano-emitter.The fabrication of this hybrid nanostructure is a near-field imprinting process based on nanoscale photopolymerization. This technique, compared with traditional near-field characterization methods, provides not only the image of the field distribution, but also enables quantification of the surface plasmon properties with sub-5nm resolution and reproduction of the exponential decay of the near-field.Under dipolar mode plasmon, the photopolymer was created anisotropically in the vicinity of the metal nanoparticle. With high concentration of dye molecules trapped in the polymer, the hybrid nano-emitter displays surface enhanced fluorescence and Raman signal that is dependent on the incident polarization. To our knowledge, this is the first achievement of the anisotropic nano-emitter based on the inhomogeneous distribution of the active molecule
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Alberti, Giovanni S. „On local constraints and regularity of PDE in electromagnetics : applications to hybrid imaging inverse problems“. Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:1b30b3b7-29b1-410d-ae30-bd0a87c9720b.
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The first contribution of this thesis is a new regularity theorem for time harmonic Maxwell's equations with less than Lipschitz complex anisotropic coefficients. By using the Lp theory for elliptic equations, it is possible to prove H1 and Hölder regularity results, provided that the coefficients are W1,p for some p = 3. This improves previous regularity results, where the assumption W1,∞ for the coefficients was believed to be optimal. The method can be easily extended to the case of bi-anisotropic materials, for which a separate approach turns out to be unnecessary. The second focus of this work is the boundary control of the Helmholtz and Maxwell equations to enforce local constraints inside the domain. More precisely, we look for suitable boundary conditions such that the corresponding solutions and their derivatives satisfy certain local non-zero constraints. Complex geometric optics solutions can be used to construct such illuminations, but are impractical for several reasons. We propose a constructive approach to this problem based on the use of multiple frequencies. The suitable boundary conditions are explicitly constructed and give the desired constraints, provided that a finite number of frequencies, given a priori, are chosen in a fixed range. This method is based on the holomorphicity of the solutions with respect to the frequency and on the regularity theory for the PDE under consideration. This theory finds applications to several hybrid imaging inverse problems, where the unknown coefficients have to be imaged from internal measurements. In order to perform the reconstruction, we often need to find suitable boundary conditions such that the corresponding solutions satisfy certain non-zero constraints, depending on the particular problem under consideration. The multiple frequency approach introduced in this thesis represents a valid alternative to the use of complex geometric optics solutions to construct such boundary conditions. Several examples are discussed.
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Boksebeld, Maxime. „Elaboration et caractérisation de nanoparticules hybrides pour la microscopie multiphotonique et la thérapie ciblée du cancer“. Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEC029/document.
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Cette thèse décrit l’élaboration de nouvelles nanosondes disposant de propriétés permettant leur utilisation pour la microscopie multiphotonique ainsi que la thérapie ciblée du cancer. Dans un premier temps, ce travail s’est concentré sur la synthèse de nanoparticules actives en optique non linéaire et pour la photothérapie. Différents types de nanoparticules ont ainsi été élaborées et caractérisées comme des nanobâtonnets d’or, des nanoparticules de carbure de silicium ou de niobate de potassium, et des nanohybrides couplant ces différentes briques de base. Les nanoparticules ont ensuite été fonctionnalisées par des biomolécules comme l’acide folique afin de leur conférer des propriétés de ciblage spécifique vis-à-vis des cellules cancéreuses. La fonctionnalisation de surface des nanoparticules a été caractérisée de manière approfondie par des techniques avancées telles que la spectroscopie infrarouge, XPS et ToF-SIMS. Dans un second temps, les propriétés optiques non linéaires et thérapeutiques de ces nanoparticules ont été étudiées. Ainsi, ces nanosondes ont été utilisées avec succès pour réaliser le marquage de cellules saines et le ciblage spécifique de cellules cancéreuses pour la microscopie multiphotonique. Enfin, les propriétés photothérapeutiques de ces nanoparticules ont également été étudiées pour réaliser la destruction photoinduite de cellules cancéreusesThis thesis describes the synthesis of new nanoprobes with properties allowing their use for cancer-targeted multiphotonic microscopy and cancer phototherapy. On the one hand, this work was focused on the synthesis of nanoparticles with non-linear optical and phototherapeutic properties. Different nanoparticles were synthesized and used like gold nanorods, silicon carbide or potassium niobate nanoparticles, and nanohybrids coupling these previous nano-building blocks. These nanoparticles were functionalized with biomolecules like folic acid to provide specific cancer-targeting properties. The surface chemistry of these nanoparticles was carefully evaluated through advanced characterization techniques such as infrared spectroscopy, XPS and ToF-SIMS. On the other hand, optical and therapeutic properties of these nanoparticles were studied. These nanoprobes were successfully used to perform healthy cells labelling and cancer cells targeting for multiphotonic microscopy. Phototherapeutic properties of our nanoparticles were also used to induce light-triggered cancer therapy
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Schell, Andreas Wolfgang. „Photonic applications and hybrid integration of single nitrogen vacancy centres in nanodiamond“. Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2015. http://dx.doi.org/10.18452/17128.
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In dieser Arbeit wird das Stickstoff-Fehlstellenzentrum (NV Zentrum) in Diamant als ein solcher Einzelphotonenemitter untersucht. Durch Benutzung eines hybriden Ansatzes werden hier NV Zentren in Diamantnanopartikeln in photonische Strukturen integriert. Zuerst wird eine aufnehmen-und-ablegen-Nanomanipulationstechnik mittels eines Rasterkraftmikroskops verwendet um einzelne NV Zentren an eine photonische Kristallkavität und eine optische Faser zu koppeln. Durch Kopplung an die photonische Kristallkavität wird die Emission der Nullphononenlinie des NV Zentrums um den Faktor 12.1 erhöht und durch Kopplung an die optische Faser entsteht eine direkt gekoppelte Einzelphotonenquelle hoher effektiver numerischer Apertur. Durch Kopplung an plamonische Wellenleiter können einzelne Oberflächenplasmon-Polaritonen nachgewiesen werden. Zweitens wird ein anderer Ansatz, die Entwicklung eines hybriden Materials, verfolgt. Hier sind die Nanodiamanten, anstatt sie auf die Strukturen von Interesse zu legen, von Anfang in dem Material enthalten, aus dem die Strukturen hergestellt werden. Mittels direktem Zweiphotonen-Laserschreiben ist es dann möglich, Kombinationen aus chipintegrierten Wellenleitern, Resonatoren und Einzelphotonenemittern zu zeigen. Um mehr über die Dynamik von NV Zentren in Nanodiamant zu erfahren und Wege zu ihrer Verbesserung zu finden, wird die Dynamik der Nullphononenlinie des NV Zentrums mittels eines Photonenkorrelationsinterferometers untersucht. Zusätzlich zu Techniken zur Herstellung photonischer und plasmonischer Strukturen werden auch Methoden zu ihrer Charakterisierung benötigt. Hier für kann es ausgenutzt werden, dass das NV Zentrum weiter nicht nur ein Einzelphotonenemitters ist, sondern es ebenso als Sensor verwendet werden kann. Das NV Zentrum wird hier verwendet, um die lokale optische Zustandsdichte in einem Rastersondenverfahren zu messen, was die Technik der dreidimensionalen Quantenemitter Fluoreszenzlebensdauermikroskopie einführt.In this thesis, one of such single photon emitters, the nitrogen vacancy centre (NV centre) in diamond, will be examined. By using different hybrid approaches, NV centres in diamond nanoparticles are integrated into photonic structures. Firstly, using a pick-and-place nanomanipulation technique with an atomic force microscope, a single NV centre is coupled to a photonic crystal cavity and an optical fibre. Coupling to the photonic crystal cavity results in an enhancement of the NV centre''s zero phonon line by a factor of 12.1 and coupling to the fibre yields a directly coupled single photon source with an effective numerical aperture of 0.82. By coupling to plasmonic waveguides, the signature of single surface plasmon polaritons is found. Secondly, instead of placing the nanodiamonds on the structures of interest, a hybrid material where the emitters are incorporated is used. With two-photon direct laser writing, on-chip integration and combination of waveguides, resonators, and single photon emitters is demonstrated. In order to learn more on the dynamics of NV centre in nanodiamonds and find ways for improvements, the dynamics of the ultra-fast spectral diffusion of the NV centre''s zero phonon line are investigated using a photon correlation interferometer. In addition to techniques for the fabrication of photonic and plasmonic structures, also methods for their characterisation are needed.For this, it can be exploited that the NV centre also is not only a single photon emitter, but can also be employed as a sensor. Here, the NV centre is used to measure the local density of optical states in a scanning probe experiment, establishing the technique of three-dimensional quantum emitter fluorescence lifetime imaging.
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Serna, Otálvaro Samuel Felipe. „Design and characterization of Silicon Photonic structures for third order nonlinear effects“. Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS409/document.
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Le présent travail a été consacré à l'étude des non linéarités de troisième ordre dans des structures intégrées à base de silicium exploitant des configurations de cavités à miroir de Bragg (nanobeam) et guides à cristaux photoniques à modes lents. Tout d'abord, nous avons développé une méthode non destructive à faisceau unique pour caractériser les effets de troisième ordre instantanés, c’est-à-dire la quantification de la susceptibilité complexe effective dans les guides d'ondes. La méthode a été dénommée "Top-hat D-Scan bi-directionnelle" et constitue un analogue temporel de la méthode Top-hat Z-Scan développée précédemment. Nous avons établi un modèle analytique et numérique et nous rendons compte de la première mesure d'un guide d'ondes en silicium utilisant une impulsion mis en forme dans un étireur et complétée par une procédure d’injection bi-directionnelle. L’ensemble instrumental développé constitue une expérience de métrologie des effets non-linéaires dans des guides d’ondes silicium au meilleur niveau de l’état de l’art. La méthode proposée a été validée dans des guides SiGe, chalcogénures et nitrure du silicium. Forts de cet outil métrologique, nos travaux d’exploration des interactions non linéaires lumière-matière ont été consacrés à deux grandes familles de nanostructures photoniques : des microcavités optiques et guides d'ondes en régime de lumière lente. Dans la première des deux situations, les variations d'indice provoquées par les non linéarités sont responsables d’un décalage des fréquences de résonance excluant sa coïncidence avec la fréquence du signal d'excitation et diminuant ainsi l'efficacité de l'injection optique de manière drastique. Afin de maintenir le bénéfice de localisation de la lumière tout au long de l'excitation pulsée, nous avons expérimentalement et numériquement étudié le comportement d'une cavité en silicium conçue, fabriquée, et enfin excitée par une impulsion présentant une puissance crête élevée. En contrôlant temporellement la phase des composantes spectrales injectée, la relation de phase spectrale compensant la dérive de fréquence non linéaire de la résonance de la cavité, nous avons effectué la première démonstration expérimentale de l'excitation cohérente d'une micro-cavité silicium non linéaire. Enfin, nous avons consacré des efforts importants pour concevoir, fabriquer et caractériser des guides d'ondes à cristaux photoniques (SPhCW) en silicium à fente, matrice d’une intégration hybride de matériaux optiques non-linéaires sur silicium. Les résultats rapportés fournissent la première preuve expérimentale d’un contrôle précis des propriétés de dispersion de guides à cristaux photoniques à fente propres à être remplis par des matériaux souples comme des polymères ou des couches minces dopées. La dispersion de groupe des modes lents guidés est contrôlable en signe et en amplitude et correspond à des bandes passantes optiques exploitables (~10nm). Ces résultats démontrent l’intérêt direct pour le traitement des données tout-optique sur puce des guides à modes lents à cœur creux utilisant des effets optiques non linéaires d’ordre trois pour le traitement tout-optique des données sur puceAll-optical signal processing implemented in silicon photonics is considered as a promising route to solve several bottlenecks for the realization of future dense and mixed integrated electronic and photonic chips including ultrahigh data bit rate issues and power consumption constraints. In the context of the planar silicon photonics technology, a dramatic reduction of the needed power to reach optical nonlinear effects is obtained due to the sub-micrometer size of silicon wires (~450nmX260nm) in the telecommunication wavelength window, although silicon does not exhibit second-order response (χ^((2))) due to the centrosymmetry of its lattice. Moreover, third-order effects (χ^((3))) are partially spoiled in this material due to the strength of the two-photon-absorption (TPA) effect, which in turn generates free-carriers inducing additional absorption and refractive index changes. One way to overcome this limitation is the hybrid integration on silicon of low index soft materials with luminescence or nonlinear optical properties lacking to silicon. In this context, the present work is devoted to the study of third order nonlinearities in silicon-based integrated structures exploiting enhanced electromagnetic field effects (e.g. in Si resonators and slow light waveguides). First, we have developed a dedicated single beam non-destructive method to characterize the instantaneous third order effects though the quantification of complex effective waveguide susceptibility. The method is named “Bi-directional top-hat D-Scan” and consists on a temporal analogous of the top-hat Z-Scan. We have established an analytical and numerical model and we report the first measurement of a silicon waveguide by using a pulse shaping set-up and a bi-directional procedure. The originality of our methods stands in the capability to measure in two steps : the 3rd order nonlinear Figure-Of-Merit (FOM) independently of the injection losses, and the effective nonlinear waveguide parameters (Kerr and TPA) taking into account measured coupling losses at each facet. Furthermore, we apply the method to other integrated novel materials including Ge-rich GeSi alloys, carbon nanotube doped thin films, and chalcogenide waveguides. Additionally, two further enhancements of light-matter nonlinear interactions have been explored within this work: optical microcavities and slow light waveguides. In the first picture, index variations caused by non-linearities shift the resonance frequencies precluding the coincidence with the excitation signal frequency, thereby decreasing the injection efficiency. In order to maintain the benefit of light localization throughout the pulsed excitation, we have experimentally and numerically studied the behavior of a designed and fabricated silicon nanobeam cavity excited by a high power tailored chirped pulse whose spectral phase relation compensates for the nonlinear frequency drift of the cavity resonance. We report a numerical study of this first experimental demonstration of the coherent excitation of a nonlinear micro-cavity, leading to an enhanced intra-cavity nonlinear interaction. Finally, we have dedicated efforts to engineer, fabricate and characterize silicon slot photonic crystal waveguides (SPhCW) in order to compensate their strong dispersion present in the slow light regime while taking benefit from large group index light propagation. We showed that their frequency dispersion properties can be engineered from anomalous to normal dispersion, along with zero group velocity dispersion (ZGVD) crossing points exhibiting a Normalized Delay Bandwidth Product (NDBP) as high as 0.156. The reported results provide the first experimental evidence for an accurate control of the dispersion properties of fillable periodical slotted structures in silicon photonics, which is of direct interest for on-chip all-optical data treatment using nonlinear optical effects in hybrid-on-silicon technologies
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Pritz, Jakub. „Biological Effective Dose (BED) Distribution Matching for Obtaining Brachytherapy Prescription Doses & Dosimetric Optimization for Hybrid Seed Brachytherapy“. Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3298.
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Radioactive seed implant brachytherapy is a common radiotherapy treatment method for prostate cancer. In current clinical practice, a seed consists of a single isotope, such as 125I or 103Pd. A seed containing a mixture of two isotopes has been proposed for prostate cancer treatment. This study investigates a method for defining a prescription dose for new seed compositions based on matching the biological equivalent dose (BED) of a reference plan.
Ten prostate cancer cases previously treated using single isotope seeds (5 using 125I seeds and 5 using 103Pd seeds) were selected for this study. Verification of the method was done by calculating prescription doses for 103Pd and 125I seeds. A prescription dose for a 50/50 hybrid seed was calculated. Number and location of seeds remained invariant within each case. The BED distributions for hybrid and single isotope seed plans were generated and matched to the BED distribution generated off of the optimized plans.
For the 125I isotopes, the dose necessary to cover 90% of the prostate with a BED of 110 Gy is 145 Gy. For the same BED coverage, the dose for 103Pd and 50/50 hybrid seed is 120 Gy and 137 Gy respectively.
A method is introduced for obtaining prescription doses for new brachytherapy sources. The method was verified by obtaining doses for 125I and 103Pd isotopes which match clinical prescription doses. The method developed is robust enough to calculate prescription doses in any region of interest, for any seed type, and for any isotope as long as the BED coverage remains invariant with respect to the treatment plan.
Numerical calculations were performed to derive analytical conversions of total dose to BED for 50/50, 75/25 and 25/75 hybrid seeds. These analytical conversions are faster than the original numerical methods employed allowing for real-time BED optimization for hybrid seeds.
Varying seed distribution was seen not to influence the analytical conversions. It was observed that when total dose remained invariant while individual isotope contributions varied, the value of BED varied. The BED variance was seen to be the smaller at larger BED values (~2% at 100 Gy).
Using the conversions derived in this paper, BED based optimization for hybrid seeds are now performable. However, these conversions should only be used in high dose regions due to high uncertainty in the low regime.
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Asenbeck, Beate Elisabeth. „Advancing Non-Gaussian states and measurements - an experimental test bed for heterogeneous quantum networks“. Electronic Thesis or Diss., Sorbonne université, 2024. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2024SORUS167.pdf.
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Cette thèse porte sur la création et la manipulation d'états non gaussiens dans le but de tester les réseaux quantiques hétérogènes émergents. Ces réseaux sont envisagés pour héberger de multiples plateformes physiques, connectées par des lignes de communication optiques. Les états optiques utilisés pour cette communication devront être adaptés à l'encodage de la plateforme physique à laquelle ils sont connectés, ce qui conduit à une variété de stratégies d'encodage possibles. Dans ce travail, nous développons des critères pour tester la qualité des différents encodages et des outils de référence qui garantissent un transfert d'informations fidèle. En outre, nous montrons que plusieurs encodages peuvent être utilisés simultanément dans le même réseau quantique sans perdre leurs propriétés quantiques lors de la conversion. Nous utilisons des oscillateurs paramétriques optiques de haute qualité, produisant des états comprimés monomodes ou bimodes. Grâce à des détecteurs à photons uniques supraconducteurs, nous créons deux encodages optiques différents représentant un système à deux niveaux et un oscillateur harmonique. Le système à deux niveaux correspond à des superpositions d'excitations de nombres de photons, tandis que l'état de l'oscillateur harmonique à des chats de Schrödinger optiques. En créant une intrication entre ces deux encodages différents, il est possible de les utiliser dans des protocoles de réseau. Ces derniers sont intrinsèquement limités par le taux de réussite et la fidélité des mesures de l'état de Bell. Nous présentons une amélioration de la fidélité de l'état de sortie et de la projectivité d'une mesure linéaire tout-optique de l'état de Bell en combinant la détection de photons uniques avec la sélection en quadrature du champ. L'utilisation de l'intrication hybride avec cette mesure hybride de l'état de Bell permet de convertir un qubit d'entrée à deux niveaux en son équivalent en oscillateur harmonique dans une configuration basée sur la téléportation. Après une analyse approfondie des résultats de l'expérience du convertisseur, nous développons un critère pour juger de la non-gaussianité des cohérences quantiques. Ce critère est appliqué à deux systèmes à deux niveaux expérimentaux différents. Enfin, des simulations démontrent qu'une future version de l'expérience pourra comprendre de la génération d'états non gaussiens corrigeables d'erreur. Ce travail encourage l'utilisation de plusieurs encodages dans les réseaux quantiques et fait progresser les méthodes de mesure et de création d'états qui élargissent les capacités des systèmes optiques pour la communication quantiqueThis thesis focuses on the creation and manipulation of Non-Gaussian states with the goal of testing emerging heterogeneous quantum networks. These networks are envisioned to host multiple physical platforms, that are connected by optical communication lines. The optical states used for this communication will have to be adapted to the encoding of the physical platform they connect to, leading to a variety of possible encoding strategies. In this work, we develop criteria to test the quality of different encodings and benchmark tools that ensure faithful information transfer. Moreover, we show that multiple encodings can simultaneously be used in the same quantum network without losing their quantum properties through conversion. We use high-quality optical parametric oscillators, producing single- or two-mode squeezed states. Together with heralding via superconducting nanowire single-photon detectors, we create two different optical encodings representing a two-level system and a harmonic oscillator. The two-level system corresponds to superpositions of photon-number excitations, while the harmonic oscillator state translates to optical Schrödinger cats. By creating entanglement between those two different encodings, its use in network protocols is possible. Network protocols are intrinsically limited by the success rate and fidelity of Bell-state measurements. We present an improvement in output state fidelity and projectivity of an all-optical linear Bell-state measurement by combining single photon detection with field quadrature selection. Employing hybrid entanglement together with this hybrid Bell-state measurement enables a two-level input qubit to be converted into its harmonic oscillator counterpart in a teleportation-based setup. After thorough analysis of the results of the converter experiment, we develop a criterion to judge the Non-Gaussianity of quantum coherences. This criterion is applied to two different experimental two-level systems. Finally, a stimulative study of the possible generation of error-correctable Non-Gaussian states points the way towards the future of this experiment. This work promotes the use of multiple encodings in quantum networks and advances measurements and state creation methods that expand the capability of optical systems for quantum communication
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Yaacoub, Saly. „Etude de couches hybrides photopolymérisables de type vinyl éther silane : Application à la fabrication de composants optiques intégrés“. Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20175/document.
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Depuis plusieurs dizaines d'années, les matériaux hybrides organiques-inorganiques constituent une classe de matériaux particulièrement bien adaptée aux applications en optique intégrée. Le réseau minéral, élaboré par procédé sol-gel, confère au matériau la tenue mécanique. Quant au réseau organique, qui est réticulable par voie photochimique, il permet la formation des systèmes guidants. Des travaux antérieurs réalisés au sein de notre laboratoire ont montré le potentiel d'un matériau à base d'un précurseur hybride 2-(3,4 epoxycyclohexylethyltrimethoxysilane) (EETMOS) pour l'application en optique intégrée. Bien que la qualité des composants réalisés à 1,31µm se soit révélée satisfaisante, un problème subsiste : une trop forte atténuation à 1,55 µm. La transmission optique autour de ces longueurs d'ondes est limitée par la présence des groupements OH et CH aliphatiques.L'objectif principal de ce travail est de développer une nouvelle génération de matériaux hybrides avec une très grande réactivité et de diminuer la quantité de groupements impliqués dans l'atténuation. Nous avons choisi la fonction vinyl éther comme fonction organique grâce à sa grande réactivité par voie cationique en comparaison avec la fonction époxyde. Nous avons étudié la double fonctionnalité de polymérisation du nouveau matériau hybride à base d'un vinyl éther silane. En premier lieu, les réactions d'hydrolyse et de polycondensation du sol ont été suivies par la spectroscopie RMN liquide du Si-29 en fonction du temps, de la température et du pH de l'eau impliquée dans l'hydrolyse. Le but était d'obtenir le plus haut taux d'oligomère multifonctionnel possible et le minium de groupement OH. La photopolymérisation de type cationique de la fonction vinyl éther a ensuite été étudiée, en utilisant la spectroscopie d'absorption dans l'infrarouge moyen. En présence du photoamorceur diaryliodonium, la photopolymérisation a été étudiée en suivant l'évolution de la bande d'absorption de la double liaison vinyl éther avant et après irradiation. La photopolymérisation cationique est rapidement initiée dès le début de l'exposition aux UV, ce qui prouve la réactivité important de la fonction vinyl éther. En utilisant la spectroscopie d'absorption dans le proche infrarouge, les résultats montrent des niveaux d'atténuation très prometteurs pour l'utilisation de ce matériau en optique intégré à 1,31 et 1,55 µmIn the last few years, organic-inorganic hybrid materials were particularly attractive for integrated optical circuits. Hybrid network could be prepared by the formation of inorganic and organic network simultaneously through sol-gel technique and photopolymerization process.A composition based on [2-(3, 4 epoxycyclohexylethyltrimethoxysilane)] has already allowed the fabrication of optical integrated devices. The organic polymerization is on a cationic way. Results show the contributions of OH and aliphatic CH groups to the attenuation in the third telecommunication window located at 1,55 µm.The main objective of this work is to remove this difficulty by developing a new generation of hybrid materials with a very high reactivity and low amount of groups involved in the attenuation. We have chosen vinyl ether function as an organic part because of their well known high polymerization rates via cationic way which are faster than the epoxide function and which lead to no OH groups generation and a very low aliphatic CH groups introduction.In this work, we study the dual functional structure of a new vinyl ether alkoxysilane hybrid precursor. Firstly, hydrolysis and polycondensation of vinyl ether based solution are followed by liquid and solid Si-NMR spectroscopy. The kinetic reaction is followed as a function of time, temperature and pH of the water involved in the hydrolysis, in order to obtain the highest reactive multifunctional oligomer and the lowest OH groups. Secondly, results of the cationic photopolymerization of vinyl ether- based monomers are also reported, using middle infrared spectroscopy. In the presence of diaryliodonium photoinitator, the photopolymerization is studied by monitoring the absorption band of vinyl ether double bond before and after irradiation. The cationic photopolymerization occurs rapidly upon UV-exposure and vinyl ether monomers proved to be very effective monomers. Using near infrared spectroscopy, results show promising attenuation for the use of this material in integrated optic at 1,31 µmand 1,55 µm
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Zhao, Mingjun. „NONINVASIVE MULTIMODAL DIFFUSE OPTICAL IMAGING OF VULNERABLE TISSUE HEMODYNAMICS“. UKnowledge, 2019. https://uknowledge.uky.edu/cbme_etds/58.
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Measurement of tissue hemodynamics provides vital information for the assessment of tissue viability. This thesis reports three noninvasive near-infrared diffuse optical systems for spectroscopic measurements and tomographic imaging of tissue hemodynamics in vulnerable tissues with the goal of disease diagnosis and treatment monitoring. A hybrid near-infrared spectroscopy/diffuse correlation spectroscopy (NIRS/DCS) instrument with a contact fiber-optic probe was developed and utilized for simultaneous and continuous monitoring of blood flow (BF), blood oxygenation, and oxidative metabolism in exercising gastrocnemius. Results measured by the hybrid NIRS/DCS instrument in 37 subjects (mean age: 67 ± 6) indicated that vitamin D supplement plus aerobic training improved muscle metabolic function in older population. To reduce the interference and potential infection risk on vulnerable tissues caused by the contact measurement, a noncontact diffuse correlation spectroscopy/tomography (ncDCS/ncDCT) system was then developed. The ncDCS/ncDCT system employed optical lenses to project limited numbers of sources and detectors on the tissue surface. A motor-driven noncontact probe scanned over a region of interest to collect boundary data for three dimensional (3D) tomographic imaging of blood flow distribution. The ncDCS was tested for BF measurements in mastectomy skin flaps. Nineteen (19) patients underwent mastectomy and implant-based breast reconstruction were measured before and immediately after mastectomy. The BF index after mastectomy in each patient was normalized to its baseline value before surgery to get relative BF (rBF). Since rBF values in the patients with necrosis (n = 4) were significantly lower than those without necrosis (n = 15), rBF levels can be used to predict mastectomy skin flap necrosis. The ncDCT was tested for 3D imaging of BF distributions in chronic wounds of 5 patients. Spatial variations in BF contrasts over the wounded tissues were observed, indicating the capability of ncDCT in detecting tissue hemodynamic heterogeneities. To improve temporal/spatial resolution and avoid motion artifacts due to a long mechanical scanning of ncDCT, an electron-multiplying charge-coupled device based noncontact speckle contrast diffuse correlation tomography (scDCT) was developed. Validation of scDCT was done by imaging both high and low BF contrasts in tissue-like phantoms and human forearms. In a wound imaging study using scDCT, significant lower BF values were observed in the burned areas/volumes compared to surrounding normal tissues in two patients with burn. One limitation in this study was the potential influence of other unknown tissue optical properties such as tissue absorption coefficient (µa) on BF measurements. A new algorithm was then developed to extract both µa and BF using light intensities and speckle contrasts measured by scDCT at multiple source-detector distances. The new algorithm was validated using tissue-like liquid phantoms with varied values of µa and BF index. In-vivo validation and application of the innovative scDCT technique with the new algorithm is the subject of future work.
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Gurley, Katelyn. „USE OF HYBRID DIFFUSE OPTICAL SPECTROSCOPIES IN CONTINUOUS MONITORING OF BLOOD FLOW, BLOOD OXYGENATION, AND OXYGEN CONSUMPTION RATE IN EXERCISING SKELETAL MUSCLE“. UKnowledge, 2012. http://uknowledge.uky.edu/cbme_etds/3.
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This study combines noninvasive hybrid diffuse optical spectroscopies [near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS)] with occlusive calibration for continuous measurement of absolute blood flow (BF), tissue blood oxygenation (StO2), and oxygen consumption rate (VO2) in exercising skeletal muscle. Subjects performed rhythmic dynamic handgrip exercise, while an optical probe connected to a hybrid NIRS/DCS flow-oximeter directly monitored oxy-, deoxy-, and total hemoglobin concentrations ([HbO2], [Hb], and [tHb]), StO2, relative BF (rBF), and relative VO2 (rVO2) in the forearm flexor muscles. Absolute baseline BF and VO2 were obtained through venous and arterial occlusions, respectively, and used to calibrate continuous relative parameters. Previously known problems with muscle fiber motion artifact in optical measurements were mitigated with a novel dynamometer-based gating algorithm. Nine healthy young subjects were measured and results validated against previous literature findings. Ten older subjects with fibromyalgia and thirteen age-matched healthy controls were then successfully measured to observe differences in hemodynamic and metabolic response to exercise. This study demonstrates a novel application of NIRS/DCS technology to simultaneously evaluate quantitative hemodynamic and metabolic parameters in exercising skeletal muscle. This method has broad application to research and clinical assessment of disease (e.g. peripheral vascular disease, fibromyalgia), treatment evaluation, and sports medicine.
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Casale, Marco. „Réalisation d'un laser DFB hybride sur substrat de verre“. Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENT011/document.
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Les besoins actuels des systèmes de télécommunications et des capteurs optiques poussent à réaliser des circuits intégrés optiques présentant toujours plus de fonctions sur un même substrat. Atteindre un tel niveau d'intégration est difficile, car les matériaux et les procédés technologiques employés pour implémenter les différentes fonctions optiques ne sont pas toujours compatibles entre eux. Cette thèse s'inscrit dans la problématique de l'intégration des fonctions optiques actives (émission, amplification) et passives (multiplexage, filtrage, etc.) sur substrat passif et reporte la réalisation d'un laser DFB hybride tridimensionnel par échange d'ions sur verre passif et report de plaque d'un verre actif codopé Er3+:Yb3+. Ce laser est constitué d'un guide canal de Bragg, sélectivement enterré dans le substrat passif, et chargé par un guide plan, réalisé dans le verre actif (dopé avec une concentration massique de 2,3% en Er2O3 et 3,6% en Yb2O3). Il est caractérisé par une émission monomode de (420±15) µW à 1534 nm, pour (390±20) mW de puissance de pompe injectée. Ce dispositif ouvre ainsi la voie vers l'intégration de fonctions actives, localisées à la surface du substrat passif, avec des fonctions passives, réalisées en exploitant le volume et la surface du même substratThe current needs of optical telecommunications and sensors require developing integrated optical circuits providing different and heterogeneous functions on the same substrate. The main issue is the incompatibility between the manufacturing processes of these optical functions. This work deals with the integration of active (emission, amplification) and passive (multiplexing, filtering, etc.) functions on a passive glass substrate. Its aim is to develop a DFB three-dimensional hybrid laser by ion-exchange in passive glass. This laser is made of a Bragg channel waveguide, selectively buried in the passive glass substrate, loaded by a plane waveguide, defined at the surface of an Er3+:Yb3+ codoped active glass wafer. It emits a (420±15) µW laser signal at 1534 nm for (390±20) mW injected pump power. Hence this device opens the way towards the integration of active functions, located at the surface of the passive glass substrate, with passive ones, spreading at its surface and in its volume