37 research outputs found
Miroirs de Bragg et microcavités en silicium poreux : effet de l'oxydation
session orale Ma1 « Composants passifs et Optique intégrée » [Ma1.1]National audienceDes structures verticales que sont des miroirs de Bragg et des microcavités ont été élaborées en silicium poreux et en silice poreuse. La silice poreuse est obtenue en oxydant le silicium poreux. Une étude préliminaire a permis d'étudier l'indice de réfraction des couches en silicium poreux avant et après oxydation, la vitesse de formation de ces couches et l'évolution de la variation de l'épaisseur après oxydation en fonction de la porosité initiale des couches. L'objectif de ce travail est d'anticiper l'évolution de la réponse spectrale de ces dispositifs due à l'oxydation
Integrated polymers (PVCi/PMATRIFE) microring resonators for low power tunable filters
International audienceIn this paper we present optical and thermo-optical characterization results of integrated filters based on micro-ring resonators fabricated with a couple of polymers ''PVCI/PMATRIFE''. Their high index contrast (Dn 0.15 at the wavelength of 1550 nm) allows to make small size waveguides with cross sections of 1.5 1.5 mm2. The study of the impact of different gaps on the extinction ratio and FWHM (full width at half maximum) of filters leads to a better design. First experiments of thermal tunability of the microring filter using a thermo-electric cooler (TEC) are also reported giving a 5 nm shift of the dropped wavelength for a temperature change of 40 K. The fabrication of gold electrodes on microrings is reported and the electrical power required for the tuning of the drop wavelength of 0.0055 nm/1 mW show that with an optimized electrode design the consumption will be low
Micro-resonators based on integrated polymer technology for optical sensing
International audienceResearch on sensors has experienced a noticeable development over the last decades especially in label free optical biosensors. However, compact sensors without markers for rapid, reliable and inexpensive detection of various substances induces a significant research of new technological solutions. The context of this work is the development of a sensor based on easily integrated and inexpensive micro-resonator (MR) component in integrated optics, highly sensitive and selective mainly in the areas of health and food. In this work, we take advantage of our previous studies on filters based on micro-resonators (MR) to experiment a new couple of polymers in the objective to use MR as a sensing function. MRs have been fabricated by processing SU8 polymer as core and PMATRIFE polymer as cladding layer of the waveguide. The refractive index contrast reaches 0.16 @ 1550 nm. Sub-micronic ring waveguides gaps from 0.5 to 1 µm have been successfully achieved with UV (i-line) photolithography. This work confirms our forecasts, published earlier, about the resolution that can be achieved. First results show a good extinction coefficient of ~17 dB, a quality factor around 104 and a finesse of 12. These results are in concordance with the theoretical study and they allow us to validate our technology with this couple of polymers. Work is going on with others lower cladding materials that will be used to further increase refractive index contrast for sensing applications
Characterization of Few Mode Fibers by OLCI Technique
International audienceAll LP modes of a few mode fiber are simultaneously characterized using phase-sensitive optical low-coherence interferometry. The differential modal group delay and absolute chromatic dispersion values of each mode are retrieved from a single measurement without spatial mode transformers
Technologie d'optique intégrée polymère au laboratoire FOTON
National audienceCet article résume le panorama de l'état de l'art des technologies d'optique intégrée polymère maitrisées au laboratoire Foton (Systèmes Photoniques) et qui sont axées sur des circuits optiques actifs et passifs. Les objectifs sont orientés vers un fort confinement du mode de propagation, la génération d'effets non linéaires, l'hybridation avec d'autres matériaux et la réduction des pertes (couplage et propagation)
Technologie d'optique intégrée au laboratoire Foton
National audienceCet article résume le panorama de l'état de l'art des technologies d'optique intégrée maitrisées au laboratoire Foton (Systèmes Photoniques) axé sur l'optique intégrée polymère active et passive, les guides en silicium et silice poreuse pour la réalisation de capteurs biologiques, ainsi que les applications des guides en verres spéciaux étudiés en collaboration avec d'autres laboratoires
Versatile Graded-Index Multi-Mode Fiber for High Capacity Single-and Multi-Mode Optical Home Network
International audienceA graded-index multi-mode fiber has been optimized to sustain a single excited mode when coupled with a standard single-mode fiber at 1310/1550nm while offering large effective modal bandwidth at 850nm under VCSEL excitations. Modeling and experimental results are presented
PMD Effects in Fiber Optic Transmission Systems
special issue « Fiber Optic Research in France » (Part II of III)International audiencePolarization mode dispersion (PMD) remains the most important limiting impairment for high bit rate transmission over optical fibers. In this article, after a brief description of PMD model and the associated statistic, we study the pulse distortion due to PMD using a powerful time-frequency diagram. This approach allows a very simple illustration of the second and high order PMD effects through effective pulse broadening. Finally, the PMD emulation issue and both electronic and optical compensation techniques are presented, that is a current field of cooperation between ENST-Bretagne and France Telecom R&D
An improvement in standard photolithography resolution based on Kirchhoff diffraction studies
Topic: Photonics and Semiconductor Device PhysicsInternational audienceThis paper demonstrates the realization of submicrometric patterns by using standard photolithography (365 nm). Significant improvements in standard photolithography resolution can be achieved with specific conditions of a very thin layer of photoresist (0.13 µm). Usually, standard photolithography has a resolution limit of about 1 µm. Firstly, using Kirchhoff diffraction theory we show that with these new conditions the theoretical resolution limit could be 0.4 µm. Secondly, in the experimental part, the realization of 0.8 µm size patterns is demonstrated