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202. Supraconductivite et plasmons de surface dans les nanotubes

Author

Kociak, Mathieu, Laboratoire de Physique des Solides (LPS), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Université Paris Sud - Paris XI, and Colliex Christian

Subjects
plasmons de surface, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], [PHYS.PHYS]Physics [physics]/Physics [physics], superconductivity, surface plasmons, supraconductivite, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], nanotubes
Abstract

In this work, we present two types of experiments on single nanotubes characterized in parallel by transmission electron microscopy. The first type of experiments was carried out on metal-carbon nanotube -metal junctions. The differential resistances of these junctions were measured at temperatures going from 50 mK to 1K. We showed that it is possible to induce by proximity effect a supercurrent within a rope or a monolayer nanotube, when the contacts are superconducting. When they are normal, an intrinsic superconducting transition in ropes of nanotubes was discovered at temperature down to 500 mK. We analyzed these results taking account the parameters modifying superconductivity in systems with a low number of channels. We thus showed the possibility of observing an ohmic and coherent transport in carbon nanotubes. In the second type of experiments, we looked for the understanding of the dielectric response of multiwalled carbon, boron nitride (BN) and tungsten disulphide (WS2) nanotubes. We made spatially resolved electron energy loss spectroscopy measurements. We first showed the adequacy of a classical description to account for the dielectric properties (1-50 eV) of nanotubes using measurements on carbon and BN nanotubes. The importance of the local anisotropy in the interpretation of the spectra was shown. The same kind of measurements, on WS2 nanotubes with different walls thickness, made it possible to show the existence of electromagnetic surface modes of well defined symmetry resulting from the coupling of the internal and external surfaces modes. A similar interpretation allowed us to analyze the dielectric response of carbon tubes within a classical theory, even when the wall is reduced to a monoatomic sheet.; Dans cet ouvrage, nous présentons deux types d'expériences sur des nanotubes uniques caractérisés parallèlement par microscopie électronique en transmission. Le premier type d'expériences a été mené sur des jonctions métal-nanotube de carbone-métal. La résistance différentielle de ces jonctions a été mesurée à des températures allant de 50 mK à 1K. Lorsque les contacts sont supraconducteurs, nous avons montré qu'il était possible d'induire par effet de proximité un supercourant au sein d'une corde ou d'un tube monoparoi. Lorsque les contacts sont normaux, nous avons pu mettre en évidence une transition supraconductrice intrinsèque dans des cordes de nanotubes à une température critique de environ 500 mK. Nous avons discuté ces résultats en prenant en compte les paramètres modifiant la supraconductivité dans des systèmes à faible nombre de canaux. Nous avons montré ainsi la possibilité d'observer un transport ohmique et cohérent dans des nanotubes de carbone. Dans le second type d'expériences, nous avons cherché à caractériser la réponse diélectrique de nanotubes multifeuillets de carbone, nitrure de Bore (BN) et de disulfure de tungstène (WS2). Pour cela, nous avons effectué des mesures de spectroscopie de perte d'énergie résolues spatialement. Nous avons d'abord montré l'adéquation d'une description classique pour rendre compte des propriétés diélectriques (1-50 eV) de nanotubes à l'aide de mesures sur des nanotubes de carbone et BN. L'importance de l'anisotropie locale dans l'interprétation des spectres a été démontrée. Les mêmes expériences menées cette fois sur des tubes de WS2 de parois d'épaisseur différentes a permis de mettre en évidence l'existence de modes électromagnétiques de surface de symétrie bien déterminée résultant du couplage des modes des surfaces internes et externes. Une même interprétation a permis de d'analyser la réponse diélectrique de tubes de carbone en termes classiques, même lorsque la paroi se réduit à un plan monoatomique.

Published
2001

203. Plasmon spectroscopy and imaging of individual gold nanodecahedra: A combined optical microscopy, cathodoluminescence, and electron energy-loss spectroscopy study

Author

European Commission, Ministerio de Ciencia e Innovación (España), Myroshnychenko, Viktor, Nelayah, J., Adamo, G., Geuquet, N., Rodríguez-Fernández, Jessica, Pastoriza-Santos, Isabel, MacDonald, K. F., Henrard, Luc, Liz-Marzán, Luis Manuel, Zheludev, N.I., Kociak, Mathieu, García de Abajo, Francisco Javier, European Commission, Ministerio de Ciencia e Innovación (España), Myroshnychenko, Viktor, Nelayah, J., Adamo, G., Geuquet, N., Rodríguez-Fernández, Jessica, Pastoriza-Santos, Isabel, MacDonald, K. F., Henrard, Luc, Liz-Marzán, Luis Manuel, Zheludev, N.I., Kociak, Mathieu, and García de Abajo, Francisco Javier

Abstract

Imaging localized plasmon modes in noble-metal nanoparticles is of fundamental importance for applications such as ultrasensitive molecular detection. Here, we demonstrate the combined use of optical dark-field microscopy (DFM), cathodoluminescence (CL), and electron energy-loss spectroscopy (EELS) to study localized surface plasmons on individual gold nanodecahedra. By exciting surface plasmons with either external light or an electron beam, we experimentally resolve a prominent dipole-active plasmon band in the far-field radiation acquired via DFM and CL, whereas EELS reveals an additional plasmon mode associated with a weak dipole moment. We present measured spectra and intensity maps of plasmon modes in individual nanodecahedra in excellent agreement with boundary-element method simulations, including the effect of the substrate. A simple tight-binding model is formulated to successfully explain the rich plasmon structure in these particles encompasing bright and dark modes, which we predict to be fully observable in less lossy silver decahedra. Our work provides useful insight into the complex nature of plasmon resonances in nanoparticles with pentagonal symmetry. © 2012 American Chemical Society.

Published
2012

204. Nanoscale mapping of plasmons, photons, and excitons

Author

European Commission, Agence Nationale de la Recherche (France), Kociak, Mathieu, García de Abajo, Francisco Javier, European Commission, Agence Nationale de la Recherche (France), Kociak, Mathieu, and García de Abajo, Francisco Javier

Abstract

The possibility has recently been reported of using spatially resolved electron energy loss spectroscopy and cathodoluminescence in scanning (transmission) electron microscopes to probe optical excitations'plasmons, photons, excitons'at a scale that could not have been considered only a few years ago. This allows these excitations to be studied at the relevant scale for the characterization of novel materials with potential applications in nanophotonics and nanoplasmonics. This review aims at describing the state-of-the art experimental and theoretical techniques of this emerging field and its major uses and applications. © 2012 Materials Research Society.

Published
2012

205. Spectral imaging of individual split-ring resonators

Author

Boudarham, Guillaume, Feth, Nils, Myroshnychenko, Viktor, Linden, Stefan, García de Abajo, Francisco Javier, Wegener, Martin, Kociak, Mathieu, Boudarham, Guillaume, Feth, Nils, Myroshnychenko, Viktor, Linden, Stefan, García de Abajo, Francisco Javier, Wegener, Martin, and Kociak, Mathieu

Abstract

We report on spectral imaging within individual silver split-ring resonators (SRRs) operating in the near infrared-visible range. We classified the optical eigenmodes from the measurement of their energies and nanometer scale spatial distributions. They are plasmonic standing waves that show great similarities with that of nanoantennas. We, however, evidenced marked differences in the near-field electric field lines' spatial distribution and the energies' dispersion. We also showed that the subwavelength defect's influence on the SRRs' eigenmodes spatial distribution is small. © 2010 The American Physical Society.

Published
2010

206. Multiphoton absorption and emission by interaction of swift electrons with evanescent light fields

Author

García de Abajo, Francisco Javier, Asenjo Garcia, Ana, Kociak, Mathieu, García de Abajo, Francisco Javier, Asenjo Garcia, Ana, and Kociak, Mathieu

Abstract

We introduce a theory to describe the interaction of swift electrons with strong evanescent light fields. This allows us to explain recent experimental results of multiple energy losses and gains for electrons passing near illuminated nanostructures. A complex evolution of the electron state over attosecond time scales is unveiled, giving rise to non-Poissonian distributions of multiphoton features in the electron spectra. Prospects for application to nanoscale-resolved transmission electron microscopy and spectroscopy are discussed. © 2010 American Chemical Society.

Published
2010

209. Spatially and spectrally resolved cathodoluminescence with fast electrons: A tool for background subtraction in luminescence intensity second-order correlation measurements applied to subwavelength inhomogeneous diamond nanocrystals

Author

Tizei, Luiz Henrique Galvão, primary, Meuret, Sophie, additional, Nagarajan, Sounderya, additional, Treussart, François, additional, Fang, Chia-Yi, additional, Chang, Huan-Cheng, additional, and Kociak, Mathieu, additional

Published
2013
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210. Plasmon Spectroscopy and Imaging of Individual Gold Nanodecahedra: A Combined Optical Microscopy, Cathodoluminescence, and Electron Energy-Loss Spectroscopy Study

Author

Myroshnychenko, Viktor, primary, Nelayah, Jaysen, additional, Adamo, Giorgio, additional, Geuquet, Nicolas, additional, Rodríguez-Fernández, Jessica, additional, Pastoriza-Santos, Isabel, additional, MacDonald, Kevin F., additional, Henrard, Luc, additional, Liz-Marzán, Luis M., additional, Zheludev, Nikolay I., additional, Kociak, Mathieu, additional, and García de Abajo, F. Javier, additional

Published
2012
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215. Single-Wire Light-Emitting Diodes Based on GaN Wires Containing Both Polar and Nonpolar InGaN/GaN Quantum Wells

Author

Jacopin, Gwénolé, primary, De Luna Bugallo, Andrés, additional, Lavenus, Pierre, additional, Rigutti, Lorenzo, additional, Julien, François H., additional, Zagonel, Luiz F., additional, Kociak, Mathieu, additional, Durand, Christophe, additional, Salomon, Damien, additional, Chen, Xiao Jun, additional, Eymery, Joël, additional, and Tchernycheva, Maria, additional

Published
2011
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216. Nanometer Scale Spectral Imaging of Quantum Emitters in Nanowires and Its Correlation to Their Atomically Resolved Structure

Author

Zagonel, Luiz Fernando, primary, Mazzucco, Stefano, additional, Tencé, Marcel, additional, March, Katia, additional, Bernard, Romain, additional, Laslier, Benoît, additional, Jacopin, Gwénolé, additional, Tchernycheva, Maria, additional, Rigutti, Lorenzo, additional, Julien, Francois H., additional, Songmuang, Rudeesun, additional, and Kociak, Mathieu, additional

Published
2011
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217. Chemical Imaging at Atomic Resolution as a Technique To Refine the Local Structure of Nanocrystals

Author

Trasobares, Susana, primary, López-Haro, Miguel, additional, Kociak, Mathieu, additional, March, Katia, additional, de La Peña, Francisco, additional, Perez-Omil, Jose A., additional, Calvino, Jose J., additional, Lugg, Nathan R., additional, D'Alfonso, Adrian J., additional, Allen, Leslie J., additional, and Colliex, Christian, additional

Published
2011
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223. TEM Nanolaboratory

Author

Kociak, Mathieu, primary, Kobylko, Mathias, additional, Mazzucco, Stefano, additional, Bernard, Romain, additional, Kasumov, Alekber Yu., additional, and Colliex, Christian, additional

Published
2008
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225. Mapping surface plasmons on a single metallic nanoparticle

Author

Nelayah, Jaysen, primary, Kociak, Mathieu, additional, Stéphan, Odile, additional, García de Abajo, F. Javier, additional, Tencé, Marcel, additional, Henrard, Luc, additional, Taverna, Dario, additional, Pastoriza-Santos, Isabel, additional, Liz-Marzán, Luis M., additional, and Colliex, Christian, additional

Published
2007
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231. Shot noise in carbon nanotubes

Author

Roche, Philippe-Emmanuel, primary, Kociak, Mathieu, additional, Ferrier, Meydi, additional, Gueron, Sophie, additional, Kasumov, Alik, additional, Reulet, Bertrand, additional, and Bouchiat, Helene, additional

Published
2003
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234. High-Resolution Imaging and Spectroscopy of MultipolarPlasmonic Resonances in Aluminum Nanoantennas.

Author

Martin, Jérôme, Kociak, Mathieu, Mahfoud, Zackaria, Proust, Julien, Gérard, Davy, and Plain, Jérôme

Subjects
*HIGH resolution imaging, *SPECTROMETRY, *PLASMONICS, *ALUMINUM, *OPTICAL antennas, *ELECTRON energy loss spectroscopy, *QUALITY factor
Abstract

We report on the high resolutionimaging of multipolar plasmonicresonances in aluminum nanoantennas using electron energy loss spectroscopy(EELS). Plasmonic resonances ranging from near-infrared to ultraviolet(UV) are measured. The spatial distributions of the multipolar resonantmodes are mapped and their energy dispersion is retrieved. The lossesin the aluminum antennas are studied through the full width at half-maximumof the resonances, unveiling the weight of both interband and radiativedamping mechanisms of the different multipolar resonances. In theblue-UV spectral range, high order resonant modes present a qualityfactor up to 8, two times higher than low order resonant modes atthe same energy. This study demonstrates that near-infrared to ultraviolettunable multipolar plasmonic resonances in aluminum nanoantennas withrelatively high quality factors can be engineered. Aluminum nanoantennasare thus an appealing alternative to gold or silver ones in the visibleand can be efficiently used for UV plasmonics. [ABSTRACT FROM AUTHOR]

Published
2014
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236. Seeing and measuring in colours: Electron microscopy and spectroscopies applied to nano-optics.

Author

Kociak, Mathieu, Stéphan, Odile, Gloter, Alexandre, Zagonel, Luiz F., Tizei, Luiz H.G., Tencé, Marcel, March, Katia, Blazit, Jean Denis, Mahfoud, Zackaria, Losquin, Arthur, Meuret, Sophie, and Colliex, Christian

Subjects
*SCANNING transmission electron microscopy, *ELECTRON energy loss spectroscopy, *CATHODOLUMINESCENCE, *OPTICAL properties, *WAVELENGTHS, *METAL nanoparticles
Abstract

Abstract: Over the past ten years, Scanning Transmission Electron Microscopes (STEM) fitted with Electron Energy Loss Spectroscopy (EELS) and/or Cathodoluminescence (CL) spectroscopy have demonstrated to be essential tools for probing the optical properties of nano-objects at sub-wavelength scales. Thanks to the possibility of measuring them at a nanometer scale in parallel to the determination of the structure and morphology of the object of interest, new challenging experimental and theoretical horizons have been unveiled. As regards optical properties of metallic nanoparticles, surface plasmons have been mapped at a scale unimaginable only a few years ago, while the relationship between the energy levels and the size of semiconducting nanostructures a few atomic layers thick could directly be measured. This paper reviews some of these highly stimulating recent developments. [Copyright &y& Elsevier]

Published
2014
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240. Nanoscale mapping of plasmons, photons, and excitons.

Author

Kociak, Mathieu and García de Abajo, Javier

Subjects
PLASMONS (Physics), SCANNING electrochemical microscopy, NANOPHOTONICS, ELECTRONIC excitation, PHOTONS
Abstract

The possibility has recently been reported of using spatially resolved electron energy loss spectroscopy and cathodoluminescence in scanning (transmission) electron microscopes to probe optical excitations—plasmons, photons, excitons—at a scale that could not have been considered only a few years ago. This allows these excitations to be studied at the relevant scale for the characterization of novel materials with potential applications in nanophotonics and nanoplasmonics. This review aims at describing the state-of-the art experimental and theoretical techniques of this emerging field and its major uses and applications. [ABSTRACT FROM AUTHOR]

Published
2012
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242. Longitudinal and Transversal Directed Overgrowth of Pentatwinned Silver Nanorods with Tunable Optical Properties

Author

Goldmann, Claire, Li, Xiaoyan, Kociak, Mathieu, Constantin, Doru, and Hamon, Cyrille

Abstract

Silver nanorods (AgNRs) with a controllable aspect ratio can be formed by templated growth from pentatwinned seeds. However, it is challenging to control the volume of the AgNRs and their aspect ratio independently because of the selective protection against growth of the lateral facets by halides. Here we demonstrate the preparation of AgNRs with tunable width via the addition of dimethyl sulfoxide (DMSO). AgNRs with custom dimensions were produced by separating the longitudinal and transverse growth in a two-step procedure. In the first step, the length is tuned by directing the overgrowth on the {111} tips of the AgNRs. In the second step, the width is adjusted by directing the overgrowth on the {100} lateral facets in the presence of DMSO. AgNRs of varying dimensions were obtained and characterized by a combination of techniques including scanning transmission electron microscopy, electron energy loss spectroscopy, and cathodoluminescence, which are, respectively, sensitive to the extinction and scattering component of the AgNRs’ response. This method allows tuning the plasmon energies, but also the ratio of the scattering and absorption contributions.

Published
2022
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247. Nanoscale Modification of WS2Trion Emission by Its Local Electromagnetic Environment

Author

Bonnet, Noémie, Lee, Hae Yeon, Shao, Fuhui, Woo, Steffi Y., Blazit, Jean-Denis, Watanabe, Kenji, Taniguchi, Takashi, Zobelli, Alberto, Stéphan, Odile, Kociak, Mathieu, Gradečak, Silvija, and Tizei, Luiz H. G.

Abstract

Structural, electronic, and chemical nanoscale modifications of transition metal dichalcogenide monolayers alter their optical properties. A key missing element for complete control is a direct spatial correlation of optical response to nanoscale modifications due to the large gap in spatial resolution between optical spectroscopy and nanometer-resolved techniques. Here, we bridge this gap by obtaining nanometer-resolved optical properties using electron spectroscopy at cryogenic temperatures, specifically electron energy loss spectroscopy for absorption and cathodoluminescence for emission, which are then directly correlated to chemical and structural information. In an h-BN/WS2/h-BN heterostructure, we observe local modulation of the trion (X–) emission due to tens of nanometer wide dielectric patches. Trion emission also increases in regions where charge accumulation occurs, close to the carbon film supporting the heterostructures. The localized exciton emission (L) detected here is not correlated to strain above 1%, suggesting point defects might be involved in their formation.

Published
2021
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