Wavelength-scale stationary-wave integrated Fourier-transform spectrometry

Spectrometry is a general physical-analysis approach for investigating light-matter interactions. However, the complex designs of existing spectrometers render them resistant to simplification and miniaturization, both of which are vital for applications in micro- and nanotechnology and which are now undergoing intensive research. Stationary-wave integrated Fourier-transform spectrometry (SWIFTS)-an approach based on direct intensity detection of a standing wave resulting from either reflection (as in the principle of colour photography by Gabriel Lippmann) or counterpropagative interference phenomenon-is expected to be able to overcome this drawback. Here, we present a SWIFTS-based spectrometer relying on an original optical near-field detection method in which optical nanoprobes are used to sample directly the evanescent standing wave in the waveguide. Combined with integrated optics, we report a way of reducing the volume of the spectrometer to a few hundreds of cubic wavelengths. This is the first attempt, using SWIFTS, to produce a very small integrated one-dimensional spectrometer suitable for applications where microspectrometers are essential

Mercantour National Park – across the borders of sea and mountains, a beacon for the protection of our natural and cultural heritage. eco.mont (Journal on Protected Mountain Areas Research)|eco.mont Vol. 2 No. 2 2 2|

With nearly 2 500 km² of protected territory, the Mercantour National Park (PNM), with its Italian neighbour, the Parco Naturale Alpi Marittime, has become a beacon for the protection of biodiversity in Europe. For over 30 years, many targeted conservation projects have been carried out across this mountainous massif at the south-western tip of the Alps. Beyond the general protection of regulated areas in the core zone of the park (963 km²), some emblematic large mammals and birds such as the alpine ibex and the bearded vulture have benefited from population reintroduction and/or reinforcement programmes, legitimizing a voluntarist conservation policy that relies on the participation of numerous scientific partners, NGOs and other regional stakeholders (farmers, hunters, etc.). The involvement of local actors has also become a key element of conservation policy. With the natural return of wolves, linked to their expansion in Italy and through the Liguria region, several European programmes bringing together environmental and agricultural stakeholders have made it possible to develop better coexistence between farmers, shepherds and this newly installed predator, which has forced changes to grazing practices. Today, PNM is at the crossroads of a number of changes. First, on the issue of scientific protocols and programmes, it particularly emphasizes their consistency across various networks, in the context of the global crisis of biodiversity. Second, the park is undergoing a major change in its mode of governance, collaborating with local actors to write a charter for the territory. These efforts towards development and a local takeover of natural resource management policy present a complex, dual challenge: to encourage initiatives and innovations from local actors in membership-based initiatives while enhancing the conservation of the natural and cultural heritage and the natural resources throughout the territory

Pedagogic organization of part-time studies in Network and Telecommunications at the bachelor level

International audience—This paper develops two aspects. For international colleagues, it explains the way it is possible to finance some students and academic programmes in partnership with companies in France. The second aspect deals with the pedagogic adaptations of classes of students organized around sandwich part-time studies. This organization takes account of the required competences for the students

Etude de micro-structures utilisant le guidage réfractif à fort confinement de la lumière

Les modes de galerie découverts par Lord Rayleigh en 1910 trouvent aujourd'hui des applications en optique intégrée sur silicium. Des cavités aux résonances extrêmes ont pu être intégrées sur silicium sur isolant (SOI) ou sur semi-conducteurs III-V. Ces composants permettent de réaliser des fonctions passives et actives pour la microélectronique, les télécommunications ou l'électrodynamique quantique en cavité. Avec ces nouvelles applications, de nouveaux composants faisant interagir le mode de galerie avec des éléments extérieurs comme un réseau de Bragg ou des guides optiques sont apparus. Les méthodes de modélisation de l'optique intégrée étant peu adaptées pour simuler ces cavités aux géométries particulières, nous avons développé deux modèles pour décrire ce type d'interaction. Le premier, basé sur le formalisme de Floquet-Bloch, permet de décrire des modes de galerie fortement perturbés par une modification géométrique de la cavité. Le second, basé sur une méthode de perturbation, permet de décrire des interactions de faible amplitude avec des objets extérieurs comme des guides optiques. Ces résultats ont été validés par une comparaison avec la méthode des différences finies en domaine temporel. Nos modèles ont ensuite été comparés aux réalisations expérimentales de fonctions passives sur SOI (filtres et démultiplexeurs) fabriquées au CEA-LETI, et de fonctions actives (Phosphure d'Indium et silice dopée Erbium) réalisées au LEOM ou au DRFMC. Nous avons ainsi pu caractériser des composants ayant des facteurs de qualité de 90000GRENOBLE1-BU Sciences (384212103) / SudocGRENOBLE INP-Phelma (381852301) / SudocSudocFranceF