Добірка наукової літератури з теми "Surface Plasmon Bands"

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Статті в журналах з теми "Surface Plasmon Bands"

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Lewandowski, Cyprian, and Leonid Levitov. "Intrinsically undamped plasmon modes in narrow electron bands." Proceedings of the National Academy of Sciences 116, no. 42 (September 27, 2019): 20869–74. http://dx.doi.org/10.1073/pnas.1909069116.

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Surface plasmons in 2-dimensional electron systems with narrow Bloch bands feature an interesting regime in which Landau damping (dissipation via electron–hole pair excitation) is completely quenched. This surprising behavior is made possible by strong coupling in narrow-band systems characterized by large values of the “fine structure” constant α=e2/ℏκvF. Dissipation quenching occurs when dispersing plasmon modes rise above the particle–hole continuum, extending into the forbidden energy gap that is free from particle–hole excitations. The effect is predicted to be prominent in moiré graphene, where at magic twist-angle values, flat bands feature α≫1. The extinction of Landau damping enhances spatial optical coherence. Speckle-like interference, arising in the presence of disorder scattering, can serve as a telltale signature of undamped plasmons directly accessible in near-field imaging experiments.
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Ke, Yan, Bin Chen, Mengen Hu, Ningning Zhou, Zhulin Huang, and Guowen Meng. "In-Situ Monitoring the SERS Spectra of para-Aminothiophenol Adsorbed on Plasmon-Tunable Au@Ag Core–Shell Nanostars." Nanomaterials 12, no. 7 (March 31, 2022): 1156. http://dx.doi.org/10.3390/nano12071156.

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Plasmon-induced photocatalysis on noble metal surfaces has attracted broad attention due to its application in sunlight energy conversion, while the selectivity of plasmonic platforms remains unclear. Herein, we present the controlled plasmon-mediated oxidation of para-aminothiophenol (p-ATP) by employing Au@Ag core–shell nanostars with tunable tip plasmons in visible–near-infrared range as reactors. In-situ Raman measurements indicate that Au@Ag core–shell nanostars essentially promote the conversion of p-ATP to 4,4′-dimercaptoazobenzene (DMAB) due to hot carriers excited by localized surface plasmon resonance. Au@Ag nanostars with plasmon modes under resonant light excitation suggested higher catalytic efficiency, as evidenced by the larger intensity ratios between 1440 cm−1 (N=N stretching of DMAB) and 1080 cm−1 shifts (C–S stretching of p-ATP). Importantly, the time-dependent surface-enhanced Raman scattering spectra showed that the conversion efficiency of p-ATP was mainly dictated by the resonance condition between the tip plasmon mode of Au@Ag core–shell nanostars and the excitation light, as well as the choice of excitation wavelength. These results show that plasmon bands of metal nanostructures play an important role in the efficiency of plasmon-driven photocatalysis.
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Menghrajani, Kishan S., Geoffrey R. Nash, and William L. Barnes. "Vibrational Strong Coupling with Surface Plasmons and the Presence of Surface Plasmon Stop Bands." ACS Photonics 6, no. 8 (July 11, 2019): 2110–16. http://dx.doi.org/10.1021/acsphotonics.9b00662.

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Itoh, Tamitake, Kazuhiro Hashimoto, and Yukihiro Ozaki. "Polarization dependences of surface plasmon bands and surface-enhanced Raman bands of single Ag nanoparticles." Applied Physics Letters 83, no. 11 (September 15, 2003): 2274–76. http://dx.doi.org/10.1063/1.1604188.

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Kim, Sungwan, Seong Kyu Kim, and Sungho Park. "Bimetallic Gold−Silver Nanorods Produce Multiple Surface Plasmon Bands." Journal of the American Chemical Society 131, no. 24 (June 24, 2009): 8380–81. http://dx.doi.org/10.1021/ja903093t.

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Pereyra, Pedro. "Photonic Transmittance in Metallic and Left Handed Superlattices." Photonics 7, no. 2 (April 18, 2020): 29. http://dx.doi.org/10.3390/photonics7020029.

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We study the transmission of electromagnetic waves through layered structures of metallic and left-handed media. Resonant band structures of transmission coefficients are obtained as functions of the incidence angle, the geometric parameters, and the number of unit cells of the superlattices. The theory of finite periodic systems that we use is free of assumptions, the finiteness of the periodic system being an essential condition. We rederive the correct recurrence relation of the Chebyshev polynomials that carry the physical information of the coherent coupling of plasmon modes and interface plasmons and surface plasmons, responsible for the photonic bands and the resonant structure of the surface plasmon polaritons. Unlike the dispersion relations of infinite periodic systems, which at best predict the bandwidths, we show that the dispersion relation of this theory predicts not only the bands, but also the resonant plasmons’ frequencies, above and below the plasma frequency. We show that, besides the strong influence of the incidence angle and the characteristic low transmission of a single conductor slab for frequencies ω below the plasma frequency ω p , the coherent coupling of the bulk plasmon modes and the interface surface plasmon polaritons lead to oscillating transmission coefficients and, depending on the parity of the number of unit cells n of the superlattice, the transmission coefficient vanishes or amplifies as the conductor width increases. Similarly, the well-established transmission coefficient of a single left-handed slab, which exhibits optical antimatter effects, becomes highly resonant with superluminal effects in superlattices. We determine the space-time evolution of a wave packet through the λ / 4 photonic superlattice whose bandwidth becomes negligible, and the transmission coefficient becomes a sequence of isolated and equidistant peaks with negative phase times. We show that the space-time evolution of a Gaussian wave packet, with the centroid at any of these peaks, agrees with the theoretical predictions, and no violation of the causality principle occurs.
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Vodnik, Vesna V., Dušan K. Božanić, Nataša Bibić, Zoran V. Šaponjić, and Jovan M. Nedeljković. "Optical Properties of Shaped Silver Nanoparticles." Journal of Nanoscience and Nanotechnology 8, no. 7 (July 1, 2008): 3511–15. http://dx.doi.org/10.1166/jnn.2008.144.

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The influence of shape and dielectric property of surrounding media on surface plasmon absorption band of silver nanoparticles was studied. Spherical silver nanoparticles (d = 5.6 nm) synthesized in water using NaBH4 as a reducing agent are transferred in non-polar solvent (chloroform) with phase-transfer reagent oleylamine. The absorption spectrum of oleylamine-capped silver nanoparticles dispersed in chloroform shows a strong surface plasmon resonance band that is 19 nm red-shifted compared to unmodified particles in water. The values for peak position and corresponding half widths are compared with theoretical calculations based on Mie theory. Prismatic and plate-like silver nanoparticles were synthesized in water using trisodium citrate as a reducing agent and cetyltrimethylammonium bromide as stabilizer. Due to structural anisotropy of prismatic and plate-like silver nanoparticles three surface plasmon resonance bands were observed in absorption spectrum. Nanocomposites consisting of non-spherical silver nanoparticles and polyvinyl alcohol exhibit different optical properties compared to water colloid. Instead of three surface plasmon bands, nanocomposite film has only one peak at 460 nm. Reason for appearance of single surface plasmon resonance band in nanocomposite film was discussed according to Maxwell-Garnet theory.
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Shattique, Muhammad R., and Maria Stepanova. "Surface Plasmon-Driven Reversible Transformation of DNA-Bound Methylene Blue Detected In Situ by SERS." Plasmonics 15, no. 2 (November 11, 2019): 427–34. http://dx.doi.org/10.1007/s11468-019-01050-4.

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Abstract We have reported the in situ surface–enhanced Raman spectroscopy (SERS) monitoring of repetitive surface plasmon–mediated chemical transformation cycles in a conjugate nanobiological system. The nanobiological conjugate comprised a gold-coated plasmonic substrate biofunctionalized with thiolated single–stranded DNA carrying a reduction-oxidation indicator methylthioninium chloride, which is also known as methylene blue (MB), in buffer solution at a neutral pH. Exposure to a 523-nm laser excitation produced pronounced SERS bands of oxidized MB. Continued exposure to the laser resulted in disappearance of the SERS bands, which can be interpreted as a reduction of MB. This occurred in the absence of electrochemical stimulation, chemical agents, or catalysts, suggesting a surface plasmon–mediated mechanism of the transformation. The oxidized form of MB was recovered by an addition of fresh buffer solution on the surface of the sample. Continued laser exposure with periodical addition of the buffer resulted in repetitive cycles of changes in the SERS pattern, which were monitored in situ. The chemical transformations of MB were preceded by a buildup of an intermediate SERS pattern, which was attributed to a transient form of MB created by selective surface plasmon-driven excitation.
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Ghoshal, Sib Krishna, N. N. Yusof, Ramli Arifin, and Asmahani Awang. "Luminescence from Erbium Doped Tellurite Glass: An Insight on Titania Nanoparticles Surface Plasmon Mediation." Solid State Phenomena 268 (October 2017): 143–47. http://dx.doi.org/10.4028/www.scientific.net/ssp.268.143.

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Weak stimulated emission cross-section of rare earth ions (REIs) as dopants inside various glass hosts are disadvantageous for practical applications and needs improvement. We determine the mechanism of Titania (TiO2) nanoparticles (TNPs) mediated Surface Plasmon Resonance (SPR) assisted modification in the spectral properties of tellurite glass doped with Erbium (Er3+) ions. Transparent and thermally stable glass samples with varying TNPs contents are synthesized using melt-quenching technique. TEM images revealed the existence of TNPs with average size ranged from 16 to 26 nm. Glass containing 0.4 mol% of TNPs displayed an enhancement in the Raman signal by a factor of 2.25, 1.83, 1.98, 1.56 and 3.58 for the bands centered at 388, 495, 673, 758, and 845 cm-1, which is attributed to the SPR assisted effects. Absorption spectra of TNPs embedded glass (devoid of erbium ions) manifested two surface plasmon (SP) bands at 552 and 580 nm. Up-conversion (UC) PL spectra showed three prominent bands centered at 525, 545, and 660 nm due to the Er3+ ion transition from the excited states to the ground state. Furthermore, glass containing 0.4 mol% of TiNPs exhibited an intensity enhancement by a factor of 30, and 28.57 (green bands) and 19.60 (red band), which are ascribed to the generation of strong local electric field mediated by SPR effect of TNPs situated in the vicinity of Er3+ ion. The presence of TNPs surface plasmon is asserted to be responsible for the alteration of the Er3+ ions absorbance and modification of the UC emission intensity. A correlation between SPR and Surface Enhance Raman Scattering (SERS) is established.
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Guo, Lun-Zhang, Cheng-Ham Wu, Ming-Fong Tsai, Fong-Yu Cheng, Vijayakumar Shanmugam, Zen-Uong Tsai, Zhiming Zhang, Tzu-Ming Liu, and Chen-Sheng Yeh. "Plasmon Resonant Two-Photon Luminescence Inducing Photosensitization and Nonlinear Optical Microscopy In Vivo by Near-Infrared Excitation of Au Nanopeanuts." Applied Sciences 11, no. 22 (November 17, 2021): 10875. http://dx.doi.org/10.3390/app112210875.

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Анотація:
Photodynamic therapy (PDT) provides a potential therapeutic approach for killing malignant cell/solid tumors, but currently approved photosensitizers (PSs) are generally excited by visible light, limiting the penetration depth in tissues. It is necessary to develop a near-infrared (NIR) responsive photodynamic platform, providing maximum tissue penetration. Here, we present a gold nanopeanut platform exhibiting dual functions of NIR PDT and two-photon luminescence imaging. The nanopeanut with a size less than 100 nm exhibits two distinct NIR surface plasmon absorption bands at approximately 1110 and 1300 nm. To perform PDT, we conjugated commercial toluidine blue O (TBO) PS on the surface of the nanopeanuts. With spectral overlap, the 1230-nm femtosecond Cr: forsterite laser can excite the surface plasmons of nanopeanuts, transfer energy to TBO, and generate singlet oxygen to kill cells. Moreover, the plasmon resonance-enhanced two-photon luminescence of nanopeanuts can be used to map their delivery in vivo. These results demonstrate that the PS-conjugated gold nanopeanut is an effective theranostic system for NIR PDT.
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Дисертації з теми "Surface Plasmon Bands"

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Laitenberger, Peter. "Structural and spectroscopic studies of surfaces." Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364531.

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Nakkach, Mohamed. "Imagerie multidimensionnelle en mode de résonance de plasmons de surface de structures de biopuces : expérience et modélisation." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00734650.

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Dans cette thèse nous avons ajouté le contrôle du paramètre spectral pour donner plus de degré de liberté à l'instrument basé sur l'Imagerie par Résonance des Plasmons de Surface (SPRI), développant un système instrumental à interrogation angulo-spectrale. Pour valider notre travail, nous avons pris comme modèle d'étude un milieu diélectrique absorbant à unelongueur d'onde visible. La fonction diélectrique complexe est traitée par le modèle de Lorentz et la relation entre la partie réelle et imaginaire de l'indice optique est assurée par la relation de Kramers-Kronig. Nous avons commencé par injecter dans la cellule de mesure un colorant absorbant à 630 nm et mesuré la réflectivité angulo-spectrale avec ce milieu. Ensuite, un programme d'ajustement, que nous avons développé, a été utilisé pour le calcul inverse et la détermination des paramètres optiques à partir des données de l'expérience. Cet ajustement permet d'extraire la partie réelle et la partie imaginaire de l'indice de réfraction démontrant la possibilité d'applications de type spectroscopique. Nous avons également intégré successivement à la surface des molécules d'ADN marquées par différents chromophores pour voir l'effet de la position d'absorption sur la variation de réflectivité angulo-spectrale. En plus des milieux absorbants, nous avons fabriqué des réseaux diélectriques et métalliques et les avons intégrés à la surface du prisme. Les structures utilisées avaient une période de 250 nm et une épaisseur de 300 nm en PMMA. Cette condition nous a permis de voir un plasmon bandgap centré à 735 nm. Cette étude expérimentale est validée par une étude théorique en utilisant la méthode RCWA pour simuler la réponse des réseaux périodiques.
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Barbet, Sophie. "Étude par microscopie à champ proche de matériaux III-N pour émetteurs électroniques planaires." Thesis, Lille 1, 2008. http://www.theses.fr/2008LIL10014/document.

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Ce travail de thèse consiste à étudier l'instrumentation de la sonde de Kelvin (KFM) sur un microscope à force atomique (AFM) commercial et ensuite à caractériser les surfaces et composants à base nitrure de gallium (GaN). Le potentiel de surface Vs, entre une pointe métallique et un matériau semiconducteur dépend de la différence de travaux de sortie des deux matériaux, des concentrations en dopants et des états de surface du semiconducteur. La technique KFM permet d'obtenir cette information à une échelle nano ou micrométrique. Ce projet a consisté à développer ce mode de mesure à partir de microscopes AFM commerciaux. L'étude de l'instrumentation a permis de montrer la présence de couplages parasites qui entachent d'erreur la mesure de Vs. Une stratégie est alors proposée pour permettre la mesure de Vs tout en s'affranchissant de ces effets parasites. Cette technique est ensuite appliquée à la caractérisation de structures à base de GaN. L'intérêt pour ce matériau semiconducteur à large bande interdite est croissant en électronique de puissance, par exemple pour la réalisation d'émetteurs électroniques de puissance. Pour étudier les propriétés électriques de ce matériau, nous avons réalisé une référence de potentiel qui nécessite le développement de contacts ohmiques sur le GaN de type n et p. A partir des valeurs de Vs mesurées par KFM, nous en déduisons la densité de charges de surface et une estimation de la densité d'états de surface du GaN. Enfin, nous avons étudié par KFM les effets de traitements de surface sur des structures MIS à base de GaN de type n, ainsi que les effets de différentes passivations sur des transistors HEMT à base d'AIGaN/GaN
The purpose of the thesis is to study GaN materials and devices with an atomic force microscopy in Kelvin Force Mode. The contact potential difference between a metal tip and a semiconducting material depends on the work function difference between the materials, the concentration of dopants, and the density of acceptor or donor surface states. KFM techniques provide this information at the nano- or micrometer scale. ln a first step, we have developed KFM measurement procedures on commercial microscopes in order to extract fully quantitative measurements of surface potentials. We have evidenced instrumental capacitive cross talks, for example between the electrostatic excitation and the microscope photodiode, which act as parasitic terms in the measurement of surface potentials, and need to be properly taken into account in order to get reliable measurements of contact potential differences. ln a second step we have studied the electrical properties of GaN surfaces, this material being of strong interest for power electronic applications such as electron emitters. To get a potential reference for KFM measurements, ohmic contacts on n and p-type GaN have been achieved. The KFM characterization of the layers shows surface-state induced band-bending at the oxidized GaN surface. From the values of surface potentials, we calculate the density of charge and estimate the density of surface states. We finally study the effects of surface treatments on n-GaN-MIS structures, as weIl as different types of passivation used in AlGaN/GaN HEMTs
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Varault, Stefan. "Modélisation et études expérimentales de structures à bande interdite électromagnétique reconfigurables intégrant des capillaires plasmas pour applications micro-ondes." Toulouse 3, 2011. http://www.theses.fr/2011TOU30079.

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Les matériaux à bande interdite électromagnétique (BIE), souvent nommés cristaux électromagnétiques, sont partie intégrante de la vaste famille des métamatériaux. Ils constituent l'objet d'études intensives depuis les deux dernières décennies suite au large éventail d'applications auxquelles ils donnent accès, souvent impossibles à obtenir avec des matériaux naturels, à l'instar de la réfraction négative. Généralement périodiques, ces structures sont caractérisées par trois paramètres principaux : la topologie du réseau, le pas du réseau, et la constante diélectrique de ses constituants. Leur périodicité permet l'ouverture de bandes de fréquence pour lesquelles la propagation des ondes est impossible, à l'image du miroir de Bragg. De plus, la forte anisotropie qui les caractérise permet le contrôle de la propagation des ondes électromagnétiques. Ils offrent ainsi des propriétés de filtrage à la fois spectral et spatial. Les applications courantes des cristaux photoniques et électromagnétiques incluent, sans toutefois y être limitées, les structures antennaires millimétriques et centimétriques, les surfaces haute impédance, les cavités résonantes, ou encore les différents dispositifs de guidage des ondes, basés sur les principes de réflexion interne totale, ou de cavités couplées. Bien que le domaine des applications technologiques potentielles s'accroisse rapidement, ces structures restent essentiellement passives. De ce fait, différents nouveaux concepts visant à leur conférer un caractère reconfigurable ont récemment émergés, que ce soit par le biais de matériaux ferroélectriques, de cristaux liquides, ou encore de composants actifs tels que les diodes ou les systèmes microélectromécaniques (MEMS), et plus récemment encore, les réseaux à base de microdécharges à plasma. Ce travail de thèse s'inscrit dans cette optique, et nous tentons d'apporter des solutions basées sur l'utilisation de capillaires à plasma pour permettre de reconfigurer, ou encore d'accorder dynamiquement ces structures, dans le domaine des microondes. En raison des pertes importantes et inévitables mises en jeu dans les plasmas, nous avons préféré limiter leur nombre en nous basant sur le contrôle de modes de défauts localisés plutôt que sur des réseaux complets de plasmas. Ces études ont été ménées à la fois de manière théoriques et expérimentales. Le travail se divise donc en deux parties. Dans un premier temps, nous développons les outils numériques adaptés à nos configurations, assez particulières puisqu'elles font intervenir des cylindres creux où règne un plasma. Nous nous basons d'abord, pour l'étude des réseaux infinis, sur la méthode des ondes planes. Souvent limitée au cas diélectrique, nous l'étendons aux cas de capillaires plasmas, et implémentons un outil complet pouvant traiter les cas classiques (tiges diélectriques, métalliques, et plasmas) comme des configurations plus particulières, tels que des cylindres bicouches impliquant deux matériaux différents. Dans le cas de réseaux finis, nous reprenons la méthode des matrices de diffraction, souvent limitée à des incidences planes et des cylindres pleins, que nous étendons au cas d'une incidence gaussienne d'abord, puis quelconque, dans le cas plus général de cylindres stratifiés. Nous implémentons également le cas des sources ponctuelles, donnant accès au calcul des densités locales d'état facilitant l'étude des modes de surface. La deuxième partie du travail concerne plutôt l'aspect expérimental de cette thèse. Des validations des outils précédents par la mesure sont d'abord présentées, basées sur l'étude de réseaux diélectriques, métalliques, et mixtes. Ces outils numériques sont ensuite mis à profit pour réaliser des structures potentielles commutables et accordables intégrant des capillaires à plasma. Une étude complète à la fois théorique et expérimentale est notamment menée sur des cavités résonantes à base de capillaires afin de dégager le type de technologie le plus adapté à la réalisation de dispositifs microondes (coupleurs, démultiplexeurs). La dernière partie concerne l'amélioration des dispositifs précédents, pour lesquels le couplage de l'onde incidente avec le réseau est assez faible, par le biais des modes de surface. Ce principe est ensuite utilisé pour créer une structure rayonnante directive dont la déviation angulaire du faisceau peut être contrôlée dynamiquement par le biais de capillaires plasma localisés à la surface du réseau
Electromagnetic bandgap structures, often called electromagnetic cristals, are parts of the wide metamaterials familly. They are the subject of intensive studies since the past two decades considering the wide range of applications to which they give access, often impossible to obtain with natural materials, like the negative refraction phenomenom. Generally periodic, these structures are caracterized by three main parameters: the array lattice type, its lattice constant, and the dielectric constant of its constituve materials. Their periodicity can give rise to frequency ranges over which the wave propagation is forbidden, as for Bragg mirors. Moreover, the high anisotropy which caracterizes these materials can allow the control of wave propagation outside these bangaps. They consequently offer both spatial and spectral filtering properties. Typical applications of photonic and electromagnetic cristals include, without being limited to, millimetric or centimetric radiative structures, high impedance surfaces, resonant cavities, or various wave guiding devices, based on total internal reflection or coupled cavities principles. Althought the field of potential technological applications grows rapidly, these structures still often remain essentially passive. As a result, various concepts aiming at bringing them reconfigurable properties have recently emerged, whether by means of ferroelectrics, liquid cristals, or localized components such as diodes or microelectromecanical systems (MEMS), and even more recently, microdischarge plasma arrays. This thesis work forms part from this perspective, and we try to bring solutions based on the use of plasma capillaries in order to achieve reconfigurable or dynamically tunable structures in the microwave regime. Because of the unavoidable losses that necessary come into play with the use of plasmas, we preffered to limit their use by working on localized defects control rather than on arrays entirely composed of plasmas. This studies were conducted both theoretically and experimantally. This work then organises itself in two main steps. Firstly, we developp numerical tools well suited to our configurations, rather special since they involve hollow cylinders where filled with plasma. We rely primarily on the plane wave expansion method for the case of infinite arrays, which we developp in details. Often limited to the dielectric case, we extend it to plasma capillaries arrays, and we implement a comprehensive tool that can handle conventionnal cases (arrays of dielectric, metallic, and plasma rods), but also more specific configurations such as bilayered cylinders involving two different materials for the coating and the core. For the finite lattice case, we make use of the scattering matrix method, which is often limited to plane wave incidences and simple cylinders. We extend it here for an incident gaussian beam, then for an arbitrary incident field, and in the more general case of stratified cylinders. We also implement the case of point sources, thus making possible the computation of the local density of states, which is of great interest in surface modes study for exemple. After these studies, we have at our disposal numerical models covering a very wide field of applications. The second part of the manuscript rather deals with the experimental aspects of this thesis work. Experimental validations of the previous numerical tools are first presented, which are based on dielectric, metallic, and hybrid arrays (containing both dielectric and metallic cylinders). The previously developped numerical tools are then used to design potential switchable and tunable structures involving plasma capillaries. A comprehensive study - both theoretical and experimental - is then conducted concerning plasma-based resonant cavities in order to identify the most suitable kind of technology for the realisation of microwave devices (couplers, demultiplexers). The last part focuses on the improvement of the previous dispositives, which suffer of a weak coupling with the incident wave, by means of surface modes. Those surface modes are then used to achieve a directive antenna whose scaning can dynamically be controlled by means of surface localised plasma capillaries
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Debord, Benoît. "Génération et micro-confinement de plasmas microondes dans des fibres optiques creuses microstructurées." Limoges, 2013. http://aurore.unilim.fr/theses/nxfile/default/63c75fb1-f102-4f88-95b0-fbfe07872238/blobholder:0/2013LIMO4045.pdf.

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Анотація:
Une association originale d'une excitation microonde non-intrusive et sans électrode avec une fibre à coeur creux à cristal photonique (HC-PCF) a permis pour la première fois la génération et le confinement d'un plasma dans une structure photonique, ouvrant ainsi l'avènement d'une nouvelle discipline : "Plasma Photonics". Ces travaux comprennent une étude théorique et expérimentale pour exacerber le "couplage inhibé" d’une HC-PCF à maille de Kagomé. Ceux-ci ont mené au développement d'une HC-PCF présentant des pertes record de 17 dB/km à 1 μm et avec une forte courbure des arches formant le contour du coeur hypocycloïdal. Les résultats démontrent que l'exacerbation de cette forme hypocycloïdale présente 3 mérites : une diminution des pertes de propagation, un recouvrement de la puissance optique avec la silice très fortement réduit et enfin l'obtention d'un meilleur contenu modal. Basée sur cette étude, une fibre Kagomé à large coeur (i. E. Un diamètre de coeur ~100 μm) et guidant efficacement autour de 488 nm a été développée afin de faciliter la génération d'un plasma microonde stable. La génération de ce dernier repose sur un système original d'excitation et de maintien par une onde de surface microonde, et a donné lieu, pour la première fois, à la génération et au confinement d'un plasma au sein du cœur micrométrique d’une HC-PCF. Malgré le fait que la température du plasma soit proche de celle de la transformation du matériau microstructuré environnant, celui-ci est préservé. Ceci est expliqué théoriquement par une dynamique du plasma particulière à ces échelles micrométriques avec un rôle important joué par une gaine de charge d'espace près de la paroi interne du coeur
A novel scheme enabling for the first time the generation and confinement of microwave plasma in a hollow-core photonic crystal fibre (HC-PCF) is achieved, thus paving the way to the advent of “Plasma photonics”. This is achieved by combining a non-intrusive and electrode-free microwave excitation with specifically designed HC-PCF. This work includes a theoretical and experimental study to enhance the "inhibited coupling" of a Kagomé cladding lattice HC- PCF. This led to the development of a HC-PCF with a record transmission loss of 17 dB/km at 1 μm, and exhibiting a hollow-core with hypocycloid contour with strong arc curvature. The results show that the enhancing of this core contour negative curvature has three virtues: the propagation losses are strongly reduced, the optical power overlap with silica core-surround is diminished and finally, a better modal content is obtained. Based on these findings, a large core (i. E. A core diameter of ~100 microns) Kagome HC-PCF and guiding around 488 nm is fabricated to facilitate the generation of stable microwave plasma. The generation of the latter is based on an original excitation and is sustained by a microwave surface-wave, which is turn led for the first time, to the generation and confinement of a plasma in the micrometric core of the HC-PCF. Despite the fact that the plasma has a temperature value close to that of the surrounding microstructured glassy material, the latter integrity is preserved. This is explained theoretically by a particular plasma dynamics at this micrometer scale with an important role played by a space charge sheath near the inner wall of the core
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6

Zeghib, Abdelhakim. "Contribution à l'étude de phénomènes de transport dans les couches minces Ni-Ag amorphes et microcristallisées." Rouen, 1987. http://www.theses.fr/1987ROUES014.

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Extension du modèle de Ziman aux alliages Ni-Ag et interprétation qualitative du comportement de la résistivité et du coefficient de température en fonction de la composition atomique d'argent. Etude de la structure de bandes de Ni-Ag à partir de mesures magnétiques. Mise en évidence d'un niveau lié virtuel dans les alliages majoritaires en argent, par la technique des plasmons de surface
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7

Montpied, Sylvie. "Contribution a l'etude de la passivation de composants sur arseniure de gallium : caracterisation de films dielectriques realises par depot en phase vapeur assiste par plasma." Clermont-Ferrand 2, 1986. http://www.theses.fr/1986CLF21020.

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Les transistors a effet champ a contact metal-semiconducteur, non passives, realises sur arseniure de gallium sont sujet a une degradation progressive de leurs performances statiques et dynamiques aux hyperfrequences. Ce defaut de fonctionnement est en parti attribue aux surfaces d'arseniure de gallium situees de part et d'autres de la grille. La stabilisation des composants requiert donc de la passivation de ces zones grace a des materiaux de haute qualite dielectrique realisant une interface stable avec gaas. Dans cette optique, les proprietes physico-chimiques et electriques de films de silice et de nitrure de silicium deposes en phase vapeur assiste par plasma sont etudiees en fonction du rapport des debits des gaz employe, de la temperature du substrat, de la puissance et de la frequence de l'excitation du plasma. . . Cette approche systematique permet de determiner des parametres de depot qui donnent des films ayant tres bonnes proprietes electriques: une resistivite de 10**(14) a 10**(16) ohm. Cm et un champ de claquage superieur a 10**(6) v/cm sont ainsi obtenus apres un recuit dont on soulignera l'importance. Apres mise au point d'une preparation de surface avant depot, la densite d'etats sur la bande interdite du semiconducteur a l'interface gaas/si::(3)n::(4) presente un minimum de 7. 10**(11) ev**(-2). Les depots ainsi optimalises sont utilises pour la passivation des transistors mesfet gaas. Le recouvrement d'un composant par une couche mince introduit une modification de ses caracteristiques statiques; celle-ci est expliquee conjointement par un effet piezo-electrique et par un effet de surface inherent au mode de depot. Suivant les resultats obtenus en tests de fiabilite, le nitrure de silicium s'avere etre le meilleur choix pour reussir la passivation du composant. De plus, des pretraitements par plasma et une meilleure adaptation du procede de fabrication au mode de passivation sont proposes pour ameliorer encore la stabilite a long terme des caracteristiques des transistors
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8

Gomes, Sobral Filho Regivaldo. "New possibilities for metallic nanoshells: broadening applications with narrow extinction bands." Thesis, 2018. https://dspace.library.uvic.ca//handle/1828/9415.

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This dissertation comprises experimental studies on the synthesis and applications of metallic nanoshells. These are a class of nanoparticles composed of a dielectric core and a thin metallic shell. Metallic nanoshells play an important role in nanotechnology, particularly in nanomedicine, due to their peculiar optical properties. The overall objectives of the dissertation were to improve the fabrication of these nanoparticles, and to demonstrate new applications of these materials in cancer research and spectroscopy. The fabrication of nanoshells is a multi-step process. Previously to our work, the procedures for the synthesis of nanoshells reported in the literature lacked systematic characterization of the various steps. The procedure was extremely time-consuming and the results demonstrated a high degree of size variation. In Chapter 3, we have developed characterization tools that provide checkpoints for each step of the synthesis. We demonstrated that it is possible to control the degree of coverage on the shell for a fixed amount of reagents, and also showed important differences on the shell growth phase for gold and silver. The synthetic optimization presented in Chapter 3 led to an overall faster protocol than those previously reported. Although the improvements presented in Chapter 3 led to a higher degree of control on the synthesis of nanoshells, the variations in the resulting particle population were still too large for applications in single particle spectroscopy and imaging. In Chapter 4, the synthesis was completely reformulated, aiming to narrow the size distribution of the nanoshell colloids. Through the use of a reverse microemulsion, we were able to fabricate ultramonodisperse silica (SiO2) cores, which translate into nanoshell colloids with narrow extinction bands that are comparable to those of a single nanoshell. We then fabricate a library of colloids with different core sizes, shell thicknesses and composition (gold or silver). The localized surface plasmon resonance (LSPR) of these colloids span across the visible range. From this library, two nanoshells (18nm silver on a 50nm SiO2 core, and 18nm gold on a 72nm SiO2 core) were selected for a proof of principle cell imaging experiment. The silver nanoshells were coated with a nuclear localization signal, allowing it to target the nuclear membrane. The gold nanoshells were coated with an antibody that binds to a receptor on the plasma membrane of MCF-7 human breast cancer cells. The nanoshells were easily distinguishable by eye in a dark field microscope and successful targeting was demonstrated by hyperspectral dark field microscopy. A comparison was made between fluorescent phalloidin and nanoshells, showing the superior photostability of the nanoparticles for long-term cell imaging. The results from Chapter 4 suggest that the nanoshells obtained by our new synthetic route present acceptable particle-to-particle variations in their optical properties that enables single particle extinction spectroscopy for cell imaging. In Chapter 5 we explored the use of these nanoshells for single-particle Surface-enhanced Raman spectroscopy (SERS). Notice that particle-to-particle variations in SERS are expected to be more significant than in extinction spectroscopy. This is because particle-to-particle SERS variabilities are driven by subtle changes in geometric parameters (particle size, shape, roughness). Two types of gold nanoshells were prepared and different excitation wavelengths (λex) were evaluated, respective to the LSPR of the nanoshells. Individual scattering spectra were acquired for each particle, for a total of 163 nanoshells, at two laser excitation wavelengths (632.8 nm and 785 nm). The particle-to-particle variations in SERS intensity were evaluated and correlated to the efficiency of the scattering at the LSPR peak. Chapter 6 finally shows the application of gold nanoshells as a platform for the direct visualization of circulating tumor cells (CTCs). 4T1 breast cancer cells were transduced with a non-native target protein (Thy1.1) and an anti-Thy1.1 antibody was conjugated to gold nanoshells. The use of a transduced target creates the ideal scenario for the assessment of nonspecific binding. On the in vitro phase of the study, non-transduced cells were used as a negative control. In this phase, parameters such as incubation times and nanoshell concentration were established. A murine model was then developed with the transduced 4T1 cells for the ex vivo portion of the work. Non-transduced cells were implanted in a control group. Blood was drawn from mice in both groups over the course of 29 days. Antibody-conjugated nanoshells were incubated with the blood samples and detection of single CTCs was achieved in a dark field microscope. Low levels of nonspecific binding were observed in the control group for non-transduced cells and across different cell types normally found in peripheral blood (e.g. lymphocytes). All positive and negative subjects were successfully identified. Chapter 7 provides an outlook of the work presented here and elaborates on possible directions to further develop the use of nanoshells in bioapplications and spectroscopy.
Graduate
2019-05-03
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9

凌顗鈞. "Surface Plasmon Resonance and Photonic Band Structure of Gyroid Metamaterials." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/53710393195728370176.

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10

Kuan-TingChen and 陳寬庭. "GaN-based Solar Devices featuring Mn-related Intermediate Band and Surface Plasmon Structure." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/fungr9.

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碩士
國立成功大學
光電科學與工程學系
105
This study is divided into two parts. In the first part, we focused on the optical and electrical characteristics of Mn-doped GaN and AlGaN as the absorption layers applied to the intermediate band solar cells. According to the transmittance spectrum, exhibited that the Mn-related band was formed within the forbidden band of GaN and AlGaN. Therefore, aside from absorbing the photons with the energy more than the bandgap of the material, the energy that higher than the difference between the intermediate band and the valence or conduction band could also be absorbed. At the result of the AM1.5G solar simulator indeed showed an obvious enhancement of the photocurrent density, as well as the energy conversion efficiency. In order to verify the existence of the intermediate band, we utilized the measurement of the electroluminescent spectra and external quantum efficiency. And using the dual laser system to analyze its electron transfer mechanism. On the other hand, Mn-doped GaN combined with surface plasmon structure applied to the photoelectrochemical system to produce the hydrogen is the second part of the study. The devices with surface plasmon structure could enhance the light trapping ability by scattering effect and adsorb the photons in visible light region result in the enhancement of the photocurrent density and the energy conversion efficiency. Furthermore, we designed the experiment by filtering the light whose wavelength is under 400nm to confirm the statement above.
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Книги з теми "Surface Plasmon Bands"

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Basu, Prasanta Kumar, Bratati Mukhopadhyay, and Rikmantra Basu. Semiconductor Nanophotonics. Oxford University PressOxford, 2022. http://dx.doi.org/10.1093/oso/9780198784692.001.0001.

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Abstract Nanometre sized structures made of semiconductors, insulators and metals and grown by modern growth technologies or by chemical synthesis exhibit novel electronic and optical phenomena due to confinement of electrons and photons. Strong interactions between electrons and photons in narrow regions lead to inhibited spontaneous emission, thresholdless laser operation, and Bose Einstein condensation of exciton-polaritons in microcavities. Generation of sub-wavelength radiation by surface Plasmon-polaritons at metal-semiconductor interfaces, creation of photonic band gap in dielectrics, and realization of nanometer sized semiconductor or insulator structures with negative permittivity and permeability, known as metamaterials, are further examples in the area of nanophotonics. The studies help develop Spasers and plasmonic nanolasers of subwavelength dimensions, paving the way to use plasmonics in future data centres and high speed computers working at THz bandwidth with less than a few fJ/bit dissipation. The present book intends to serveas a textbook for graduate students and researchers intending to have introductory ideas of semiconductor nanophotonics. It gives an introduction to electron-photon interactions in quantum wells, wires and dots and then discusses the processes in microcavities, photonic band gaps and metamaterials and related applications. The phenomena and device applications under strong light-matter interactions are discussed by mostly using classical and semi-classical theories. Numerous examples and problems accompany each chapter.
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Частини книг з теми "Surface Plasmon Bands"

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Popescu, L., G. Ababei, D. Babusca, D. Creanga, C. A. Benchea, N. Lupu, and L. Oprica. "Spectral Investigation of Surface Plasmon Resonance Bands of Silver Nanoparticles Capped with Gallic Acid." In IFMBE Proceedings, 305–9. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-31866-6_59.

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Ivanov, O. A., and V. A. Koldanov. "Pulsed discharges produced by surface waves in 3-cm wavelength band in the air." In Advanced Technologies Based on Wave and Beam Generated Plasmas, 511–12. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-017-0633-9_41.

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3

Charlé, K. P., W. Schulze, and B. Winter. "The size dependent shift of the surface plasmon absorption band of small spherical metal particles." In Small Particles and Inorganic Clusters, 471–75. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-74913-1_108.

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Kavetskyy, T. S., M. M. Kravtsiv, G. M. Telbiz, V. I. Nuzhdin, V. F. Valeev, and A. L. Stepanov. "Surface Plasmon Resonance Band of Ion-Synthesized Ag Nanoparticles in High Dose Ag:PMMA Nanocomposite Films." In NATO Science for Peace and Security Series B: Physics and Biophysics, 43–47. Dordrecht: Springer Netherlands, 2018. http://dx.doi.org/10.1007/978-94-024-1298-7_5.

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5

Dhara, Sandip. "Surface Plasmon Polariton Assisted Optical Switching in Noble Metal Nanoparticle Systems: A Sub-Band Gap Approach." In Reviews in Plasmonics, 1–17. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-24606-2_1.

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6

Basak, Tista, and Tushima Basak. "Recent Advances in Graphene Based Plasmonics." In Photonic Materials: Recent Advances and Emerging Applications, 56–84. BENTHAM SCIENCE PUBLISHERS, 2023. http://dx.doi.org/10.2174/9789815049756123010007.

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Plasmonics is an emerging and fast-growing branch of science and technology that focuses on the coupling of light to the free electron density in metals, resulting in strong electromagnetic field enhancement due to confinement of light into sub-wavelength dimensions beyond the diffraction limit. The development of novel photonic and optoelectronic devices based on metal-based plasmonics is however plagued by the high loss at optical frequencies, originating partly from inter-band electronic transitions and lack of electrical tunability, practically limiting their potential applications in the terahertz (THz) and mid-IR spectrum range. The recent successful exfoliation of graphene from graphite has rendered a breakthrough in the realm of plasmonics due to its phenomenal properties such as exceptionally tight light confinement, extremely long plasmon lifetime, high carrier mobility leading to a relatively low level of losses, strong optical nonlinearity and electrostatically as well as chemically tunable response. These versatile features of graphene can effectively address the challenges faced by metals, and hence the physics and potential applications of graphene-based plasmonics have triggered increasing attention of industry, academic and research fraternity in recent years. This chapter provides a comprehensive description of the theoretical approaches adopted to investigate the dispersion relation of graphene surface plasmons, types of graphene surface plasmons and their interactions with photons, phonons and electrons, experimental techniques to detect surface plasmons, the behaviour of surface plasmons in graphene nanostructures and the recent applications of graphene-based plasmonics.
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7

Shukrullah, Shazia, Muhammad Anwar, Muhammad Yasin Naz, and Inzamam Ul Haq. "Biosynthesis of Silver Nanoparticles for Study of Their Antimicrobial Effect on Plasma-Treated Textiles." In Emerging Developments and Applications of Low Temperature Plasma, 149–66. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-7998-8398-2.ch008.

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Dielectric barrier discharges (DBD) are the configurations for the production of electrical discharges using a dielectric medium between the metallic electrodes. Plasma treatment produces negative radicals, which increase the adhesion of fabric for nanoparticles. The plasma treatment made the fabric surface rougher because of the etching effect. UV-vis spectra of the Plasmon resonance band observed at 253-400 nm. X-ray diffraction results showed that AgNPs has a cubical structure and the average crystalline size is 25 nm. SEM results determined that the morphology of the silver nanoparticles are flower shaped. The energy bandgap of AgNPs was observed at 2.59 eV. The silver nanoparticles were found to have enhanced antimicrobial properties and showed better zone of inhibition against isolated bacteria (Escherichia coli). DBD plasma treatment changed the chemical as well as physical properties of the cotton fabric. FTIR spectrum revealed that oxygen-containing groups, such as C-O, C=O, O-C-O, as well as O-C=O, increased on DBD treatment of cotton samples.
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Hlali, Aymen, and Hassen Zairi. "Non-Reciprocal Series-Fed Microstrip Patch Antenna Array Based on Graphene-Black Phosphorus for THz Applications Using the Iterative Method." In Handbook of Research on 5G Networks and Advancements in Computing, Electronics, and Electrical Engineering, 165–80. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-6992-4.ch006.

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Two-dimensional materials have already demonstrated their potential in electronic applications. In this chapter, the authors propose and investigate a non-reciprocal series-fed microstrip patch antenna array based on graphene-black phosphorus for THz applications. The modeling and simulation of this structure are made with the wave concept iterative process method, in which the 2D materials are incorporated as conductive surface boundaries. Combining the advantages of graphene and BP, the antenna exhibits both strong anisotropic and plasmon responses that are not available in either individual graphene or black phosphorus layer. The authors envision that this strategy of hybridization of graphene and BP may pave the way towards non-reciprocal plasmonic components with enhanced functionalities at THz band with important applications in imaging and communications.
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Awad, Ehab. "Infrared Nano-Focusing by a Novel Plasmonic Bundt Optenna." In Plasmonics [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.104695.

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Infrared optical detection devices such as photodetectors, solar cells, cameras, and microbolometers are becoming smaller in size with a tiny active area in the range of a few micrometers or even nanometers. That comes at the expense of a smaller aperture area of the device, and in turn inefficient collection of infrared energy. Therefore, infrared plasmonic optical antennas are becoming essential to efficiently collect optical energy from free space and concentrate it down to the device’s tiny area. However, it is desirable to develop plasmonic antennas with a broad bandwidth, polarization insensitivity, wide field-of-view, and reasonable plasmonic losses. That ensures collection of most incident infrared radiation and enhancement of power absorption efficiency. In this chapter, some types of plasmonic antennas are explored with an emphasis on innovative type of optical antenna called Bundt Optenna. We investigate Bundt Optenna design and optimization. This antenna has a novel shape that looks like a Bundt baking pan and it is made of gold. Several Bundt unit cells can be arranged in a periodic array that is placed on top of a thin-film infrared absorbing layer. The Bundt Optenna utilizes surface plasmons to squeeze both electric and magnetic fields of infrared radiation down to a 50 nm wide area, thus enhancing absorption efficiency within an underneath thin-film layer. The Optenna demonstrates polarization insensitivity and ultra-broad bandwidth with a large fractional bandwidth within the near, short-wave, and mid-wave infrared bands. It also shows a remarkable enhanced power absorption efficiency and a wide field-of-view.
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Kenyon, Ian R. "Electrons in solids." In Quantum 20/20, 75–94. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198808350.003.0005.

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Electron energy bands in solids are introduced. Free electron theory for metals is presented: the Fermi gas, Fermi energy and temperature. Electrical and thermal conductivity are interpreted, including the Wiedermann–Franz law. The Hall effect and information it brings about charge carriers is discussed. Plasma oscillations of conduction electrons and the optical properties of metals are examined. Formation of quasi-particles of an electron and its screening cloud are discussed. Electron-electron and electron-phonon scattering and how they affect the mean free path are treated. Then the analysis of crystalline materials using electron Bloch waves is presented. Tight and weak binding cases are examined. Electron band structure is explained including Brillouin zones, electron kinematics and effective mass. Fermi surfaces in crystals are treated. The ARPES technique for exploring dispersion relations is explained.
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Тези доповідей конференцій з теми "Surface Plasmon Bands"

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Vallejo-Hernández, Miguel Ángel, and Janet Elías. "Transparent glass materials for gamma radiation shielding." In Frontiers in Optics. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/fio.2022.jtu5a.65.

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Glass matrices with transition metals were synthesized. Radiation shielding and optical parameters are studied. We show the characteristic surface-plasmon bands Radiation shielding parameters were calculated to analyze which sample has the best radiation shielding response.
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Wong, Jun Kai, Robert Taylor, Sungchul Baek, Yasitha Hewakuruppu, Xuchuan Jiang, and Chuyang Chen. "Temperature Measurements of a Gold Nanosphere Solution in Response to Light-Induced Hyperthermia." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-66424.

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Gold nanospheres (GNSs), biocompatible nanoparticles that can be designed to absorb visible and near-infrared light, have shown great potential in induced thermal treatment of cancer cells via Plasmonic Photothermal Therapy (PPTT) [3]. In this study, light induced heating of a water-based dispersion of 20 nm diameter GNSs was investigated at their plasmon resonance wavelength (λ = 520 nm). Temperature changes of the solution at the point of light irradiation were measured experimentally. A heat transfer model was used to verify the experimental data. The effect of two key parameters, light intensity and particle concentration, on the solution’s temperature was investigated. The experimental results showed a significant temperature rise of the GNS solution compared to de-ionized water. The temperature rise of GNS solution was linearly proportional to the concentration of GNS (from 0.25–1.0 C, C = 1×1013 particles per ml) and the light intensity (from 0.25 to 0.5 W cm−2). The experimental data matches the modeling results adequately. Overall, it can be concluded that the hyperthermic ablation of cancer cells via GNS can be achieved by controlled by the light intensity and GNS concentration. A novel component of this study is that a high power lamp source was used instead of a high power laser. This means that only low cost components were used in the current experimental set-up. Moreover, by using suitable filters and white light from the high power lamp source, it is possible to obtain light in many wavelength bands for the study of other nanoparticles with different plasmon wavelength ranges. The current results represtent just one example in this versatile experimental set-up developed. It should be noted, however, the plasmon resonance wavelength used in this study is not within the therapeutic window (750–1300 nm) [13]. Therefore, the GNSs used in this experiment are only applicable to the surface induced thermal treatment of cancer cells, for instance, in the skin.
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Liu, Liangliang, Zhuo Li, Pingping Ning, Bingzheng Xu, Chen Chen, and Changqing Gu. "A band-pass plasmonic filter based on spoof surface plasmon polaritons." In 2015 9th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics (METAMATERIALS). IEEE, 2015. http://dx.doi.org/10.1109/metamaterials.2015.7342480.

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Chen, Zhao-Min, Lei Zhao, Xinhua Liang, Yuan Li, Jiahao Zhu, Wen Jiang, Jun Wang, and Wenhua Yu. "A Band-Stop Plasmonic Filter Based on Spoof Surface Plasmon Polaritons." In 2019 International Applied Computational Electromagnetics Society Symposium - China (ACES). IEEE, 2019. http://dx.doi.org/10.23919/aces48530.2019.9060606.

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Takeuchi, Yuki, Kotaro Mukaiyama, Nobuyuki Takeyasu, and Yasutaka Hanada. "Multi-photon induced plasmon chemical transformation for laser microfabrication." In JSAP-OSA Joint Symposia. Washington, D.C.: Optica Publishing Group, 2019. http://dx.doi.org/10.1364/jsap.2019.18a_e208_6.

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Surface plasmon polaritons (SPPs) enable the light to confine to sub-wavelength space. Metallic nanostructure is often used for plasmonic device since plasmon resonance band is generally formed at visible regime. SPPs lead to several orders enhancement of incident light intensity at the metallic nanosurface. While this remarkable effect has been studied for useful application (e.g. SERS, TERS photoluminescence, etc.), it was found plasmon generated highly energetic carriers through Landau damping, referred as hot electrons and holes. The hot carrier induces chemical transformation of molecules at the plasmonic nanosurface. The fact chemically inert molecules reacted by hot carrier has been reported in the recent [1].
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Mota, R. P., I. A. Perrenoud, R. Y. Honda, M. A. Algatti, M. E. Kayama, K. G. Kostov, T. Sadahito China, and N. C. Cruz. "Biocompatible thin films obtained from Heparim-methane plasma process." In 13th International Conference on Plasma Surface Engineering September 10 - 14, 2012, in Garmisch-Partenkirchen, Germany. Linköping University Electronic Press, 2013. http://dx.doi.org/10.3384/wcc2.368-371.

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Heparin is an appropriate molecule to suppress the thrombus formation in the initial stages of blood contact with an artificial material. Therefore the covering of a synthetic material with heparin-like molecules is a great importance issue in biomaterial science and engineering. In order to reach this goal this paper deals with the plasma deposition of thin heparin-like films on microscope slides from RF-excited heparin/methane low pressure plasmas. Plasma were excited by a RF-power supply operating on 13.56 MHz at a fixed power of 50 W. Heparin was diluted in ethanol and fed into the plasma chamber in mixtures of 50% of CH4 (in pressure) at 10 Pa. Films molecular structure was characterized by Fourier transform infrared spectroscopy (FTIR here in). Molecular spectra presented absorption bands due C-H, O-H and C-O stretching and bending modes. Films surface wettability was investigated by contact angle measurements. The experimental results show values varying from 650 to 200. Surfaces optical microscopy showed the occurrence of heparin islands distributed almost uniformly over the _lm. The bloods coagulation time placed in contact with glass substrate covered by plasma deposited heparin/methane films was measured by thrombosis time and activated thromboplastin.
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Lan, Yu, Yuehang Xu, Shuxiang Li, Tengda Mei, Binbin Lv, Yong Zhang, Bo Yan, and Ruimin Xu. "An X-band surface plasmons frequency selective surface based on spoof localized surface plasmons resonators." In 2017 IEEE/MTT-S International Microwave Symposium - IMS 2017. IEEE, 2017. http://dx.doi.org/10.1109/mwsym.2017.8059057.

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Lasky, P. J., P. H. Lu, Y. Luo, R. M. Osgood, and D. A. Slater. "The Surface Preparation and Photochemistry of CdTe(110)." In Microphysics of Surfaces: Nanoscale Processing. Washington, D.C.: Optica Publishing Group, 1995. http://dx.doi.org/10.1364/msnp.1995.mfb2.

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Анотація:
Wide-band-gap II-VI compound semiconductors show great promise for the fabrication of LED's and lasers in the visible range [1]. In this paper we examine fundamental aspects of the processing of the surfaces of such materials, specifically the CdTe(110), surface, utilizing Electron Cyclotron Resonance (ECR) generated plasmas and laser-induced photochemical reactions.
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Chen, Xiangli, and Jyoti Mazumder. "Optical emission diagnostics of laser-induced graphite plasma for diamondlike film deposition." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/oam.1990.fc5.

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Анотація:
Motivated by recent interest in laser graphite ablation for optical-quality diamondlike carbon-film deposition, we took emission spectra from a pulsed KrF (3 x 108 W/cm2) excimer laser-induced plasma plume on the surface of bulk graphite. A 0.3 m spectrograph and an optical multichannel analyzer (OMA) were used. In the visible region the plasma emission was dominated by the D-A swan and C-A DesIandres-d'Azambuja bands of C2 and the B-X violet band of CN. No evidence of transitions attributable to C+, C, C3, or larger carbon clusters was found. From the band emission intensity, the vibrational temperatures of the radicals were calculated from the Einstein spontaneous emission coefficients with an assumed Boltzmann population distribution. The results from the different transitions of the C2 swan and CN violet bands all fell within the range of experimental error and uncertainty error in the Einstein coefficients and indicate a vibrational temperature of (13.5 ± 1.3) x 103 K for both radicals. This excellent agreement makes one believe that the species in the plasma are likely to be in local thermodynamic equilibrium. C2 radical concentration is estimated to be 1 × 1015 cm−3 on the basis of emission intensity and Boltzmann distribution at the above temperature.
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Pandit, Nidhi, and Nagendra Prasad Pathak. "Reconfigurable Spoof Surface Plasmon Polaritons Based Band Pass Filter." In 2018 IEEE/MTT-S International Microwave Symposium - IMS 2018. IEEE, 2018. http://dx.doi.org/10.1109/mwsym.2018.8439279.

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