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Dataset for Design of Plasmonic Directional Antennas via Evolutionary Optimization
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P.R. Wiecha, C. Majorel, C. Girard, A. Cuche, V. Paillard, O.L. Muskens & A. Arbouet. (2019). Design of plasmonic directional antennas via evolutionary optimization. Optics Express</span
High index dielectric nanostructures: From directional scattering to electric/magnetic local density of optical states control
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Photons Uniques et Nanostructures Métalliques ou Diélecriques, vers la Nano-OptiqueQuantique
No full textSondes actives pour l'optique en champ proche à base de nanoparticules isolantes ou de nanodiamants fluorescents
No full textIn the " aperture NSOM " configuration, the optical resolution is limited to 50-100 nm in the best cases. In order to probe the optical properties of systems which exhibit dimensions at the nanoscale, a better optical resolution would be advantageous. To reach this goal, we suggest the use of an optical active probe. This kind of probe is based on a fluorescent nano-emitter grafted at the apex of a classical dielectric optical probe. The resolution expected in the optical near-field should be ultimately only limited by the size of the nano-object, that is well below 50 nm. On the basis of previous works done in our laboratory, we present here two new methods for obtaining such optical active probes. These new probes involve two complementary kinds of nanoparticles with attractive sizes and good optical properties (like high emission rate in the visible and excellent photostability). The first method implies YAG nanoparticles synthesized and deposited at the apex of a probe using LECBD (Low Energy Cluster Beam Deposition). The second approach is based on the in situ selection of a nanodiamond hosting color centers (NV) which is attached onto the tip with the help of a charged polymer. Finally, we report on the realization of a room-temperature scanning single-photon probe based on a 20 nm nanodiamond hosting a single NV center, which has been successfully used for NSOM imaging. Such tips should ultimately offer a better resolution than classical optical near-field probes, and should also open new perspectives in various fields like quantum optics/plasmonics or high-resolution, high-sensitivity magnetometry.Dans la configuration dite " NSOM à ouverture ", la résolution optique est dans le meilleur des cas comprise entre 50 et 100 nm. Afin de sonder les propriétés optiques de nanosystèmes, aux dimensions toujours plus petites, une résolution optique plus fine est souhaitable. Pour remplir cet objectif, la solution que nous proposons est l'utilisation d'une sonde active. Une telle sonde repose sur le greffage d'un nano-objet fluorescent à l'apex d'une pointe optique classique. En théorie, la résolution latérale en champ proche devrait être dictée par la taille de ce nano-émetteur (<< 50 nm). Sur la base des travaux réalisés précédemment dans le laboratoire, nous présentons ici deux nouvelles méthodes pour réaliser une telle sonde. Celles-ci impliquent deux types de nanoparticules complémentaires à la taille et aux propriétés optiques attrayantes (forte émission dans le visible, photostabilité). Une première approche a été développée à partir d'un ensemble de nanoparticules de YAG, dopées par des ions cérium, produites et déposées en bout de pointe par LECBD (Low Energy Cluster Beam Deposition). La seconde approche consiste à sélectionner et à fixer en bout de pointe de manière contrôlée (grâce à un polymère) un nanodiamant, contenant des centres colorés (NV), déposé sur une lame de microscopie. L'avancement des travaux est présenté pour les deux types de nano-objets. La mise au point et l'utilisation pour l'imagerie NSOM d'une sonde active à photons uniques, basée sur nanodiamant de 20 nm contenant un seul centre NV et fonctionnant à température ambiante, sont aussi discutées. Au-delà du gain en résolution que peut apporter une telle sonde, ce nouveau type de pointe à photons uniques ouvre de nouvelles perspectives aussi bien en optique et plasmonique quantiques qu'en magnétométrie à haute résolution et haute sensibilité
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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