In-plane remote photoluminescence excitation of carbon nanotube by propagating surface plasmon

In this work, we demonstrate propagating surface plasmon polariton (SPP) coupled photoluminescence (PL) excitation of single-walled carbon nanotube (SWNT). SPPs were launched at a few micrometers from individually marked SWNT, and plasmon-coupled PL was recorded to determine the efficiency of this remote in-plane addressing scheme. The efficiency depends upon the following factors: (i) longitudinal and transverse distances between the SPP launching site and the location of the SWNT and (ii) orientation of the SWNT with respect to the plasmon propagation wave vector (k SPP). Our experiment explores the possible integration of carbon nanotubes as a plasmon sensor in plasmonic and nanophotonic devices

Spontaneous hot-electron light emission from electron-fed optical antennas

Nanoscale electronics and photonics are among the most promising research areas providing functional nano-components for data transfer and signal processing. By adopting metal-based optical antennas as a disruptive technological vehicle, we demonstrate that these two device-generating technologies can be interfaced to create an electronically-driven self-emitting unit. This nanoscale plasmonic transmitter operates by injecting electrons in a contacted tunneling antenna feedgap. Under certain operating conditions, we show that the antenna enters a highly nonlinear regime in which the energy of the emitted photons exceeds the quantum limit imposed by the applied bias. We propose a model based upon the spontaneous emission of hot electrons that correctly reproduces the experimental findings. The electron-fed optical antennas described here are critical devices for interfacing electrons and photons, enabling thus the development of optical transceivers for on-chip wireless broadcasting of information at the nanoscale

Multilayer multifunctional advanced coatings for receivers of concentrated solar power plants

International audienceThe extending market of concentrated solar power plants requires high-temperature materials for solar surface receivers that would ideally heat an air coolant beyond 1300 K. This work presents investigation on high-temperature alloys with ceramic coatings (AlN or SiC/AlN stacking) to combine the properties of the substrate (creep resistance, machinability) and of the coating (slow oxidation kinetics, high solar absorptivity). The first results showed that high temperature oxidation resistance and optical properties of metallic alloys were improved by the different coatings. However, the fast thermal shocks led to high stress levels not compatible due to the differences in thermal expansion coefficients

Study of behavior of multi-functional and multilayered coatings at high temperature

Cette thèse a pour contexte l’étude des matériaux structuraux pour les récepteurs solaires des centrales solaire à tour. Les superalliages à base nickel, les alliages à base Fe-Cr-Al, et les alliages à base Mo-Si-Al semblent tout indiqué pour cette application, car ceux-ci possèdent de bonnes propriétés mécaniques, et une bonne tenue face à l’oxydation au-delà de 1000 K. Cependant, un revêtement est nécessaire afin d’optimiser les propriétés radiatives (critère essentiel). Ainsi, ce travail a plusieurs objectifs. En premier lieu, l’oxydation des alliages nus et revêtus de céramique (AlN et/ou SiC) y est étudiée, ainsi que la tenue des revêtements sur les divers substrats. Pour cela, un four résistif et un réacteur solaire (REHPTS) ont été utilisés dans ce but, et des techniques de caractérisation (DRX, MEB, EDS, Raman, XPS) ont permis de déterminer le comportement face à l’oxydation. Le deuxième objectif est de caractériser les propriétés radiatives de ces matériaux, et leur évolution avec l’oxydation et avec la température.The context of this thesis is the study of structural materials for solar receivers in central receiver system. The Ni-based superalloys, the alloys based on Fe-Cr-Al, and the alloys based on Mo-Si-Al seems to be the best candidate to be used at high temperature for this application, because their mechanical properties and their oxidation resistance above 1000 K are very good. However a coating is necessary in order to optimize the radiative properties, which is an essential criterion. This work has thus two objectives. First as received and coated with ceramic (AlN and/or SiC) alloy samples are oxidized to study their behavior, and to study the hold of the ceramic on various substrates. For that purpose, an electrical muffle furnace and a solar reactor (REHPTS) were used, and various characterization techniques (XRD, SEM, EDS, Raman, and XPS) have allowed to determine the oxidation resistance. The second aim is to measure the radiative properties of the materials, and to characterize the impact of the oxidation and the temperature on these properties

Etude du comportement de revêtements multicouches multifonctionnels à haute température

The context of this thesis is the study of structural materials for solar receivers in central receiver system. The Ni-based superalloys, the alloys based on Fe-Cr-Al, and the alloys based on Mo-Si-Al seems to be the best candidate to be used at high temperature for this application, because their mechanical properties and their oxidation resistance above 1000 K are very good. However a coating is necessary in order to optimize the radiative properties, which is an essential criterion. This work has thus two objectives. First as received and coated with ceramic (AlN and/or SiC) alloy samples are oxidized to study their behavior, and to study the hold of the ceramic on various substrates. For that purpose, an electrical muffle furnace and a solar reactor (REHPTS) were used, and various characterization techniques (XRD, SEM, EDS, Raman, and XPS) have allowed to determine the oxidation resistance. The second aim is to measure the radiative properties of the materials, and to characterize the impact of the oxidation and the temperature on these properties.Cette thèse a pour contexte l’étude des matériaux structuraux pour les récepteurs solaires des centrales solaire à tour. Les superalliages à base nickel, les alliages à base Fe-Cr-Al, et les alliages à base Mo-Si-Al semblent tout indiqué pour cette application, car ceux-ci possèdent de bonnes propriétés mécaniques, et une bonne tenue face à l’oxydation au-delà de 1000 K. Cependant, un revêtement est nécessaire afin d’optimiser les propriétés radiatives (critère essentiel). Ainsi, ce travail a plusieurs objectifs. En premier lieu, l’oxydation des alliages nus et revêtus de céramique (AlN et/ou SiC) y est étudiée, ainsi que la tenue des revêtements sur les divers substrats. Pour cela, un four résistif et un réacteur solaire (REHPTS) ont été utilisés dans ce but, et des techniques de caractérisation (DRX, MEB, EDS, Raman, XPS) ont permis de déterminer le comportement face à l’oxydation. Le deuxième objectif est de caractériser les propriétés radiatives de ces matériaux, et leur évolution avec l’oxydation et avec la température

Excitation of a one-dimensional evanescent wave by conical edge diffraction of surface plasmon

International audienceThe experimental observation of a one-dimensional evanescent wave supported by a 90◦ metal edge is reported. Through a measurement of in-plane momenta, we clearly demonstrate the dimensional character of this surface wave and show that it is non-radiative in the superstrate. Excitation conditions, lateral extension and polarization properties of this wave are discussed. Finally, we explore the effect of the surrounding dielectric medium and demonstrate that a single edge can sustain distinct excitations

Aluminium nitride based coatings for high temperature solar reciever systems

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Etude de la tenue à l’oxydation du Kanthal Super ER pour les récepteurs solaires très hautes températures

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Materials for very high temperature solar receivers

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