Ingénierie de mode en optique intégrée sur silicium sur isolant

This thesis enters upon the localization and the handling of the light at the wavelength scale. The work initially concerned microcavities with high quality factors (Q) integrated on ridge waveguides relying on a substrate (SOI). Thanks to a mode engineering based on modes profiles adaptation, the optimization of mirrors permits us to achieve Q factors up to 60000 for a modal volume of 0,6 (lambda/n)3. Optical confinement could be observed by near-field microscopy and we showed that it was possible to control these cavities by a SNOM tip. Lastly, we investigate the slow modes approach by tackling theoretically the issue of the injection of light in slow modes.Cette thèse porte sur la localisation et la manipulation de la lumière à l'échelle de la longueur d'onde. Les travaux ont d'abord porté sur des micro-cavités à grands facteurs de qualité (Q) intégrées sur des guides rubans reposant sur un substrat (SOI). L'optimisation des miroirs grâce à une ingénierie de mode basée sur l'adaptation des profils des modes, a permis d'obtenir des Q allant jusqu'à 60000 pour un volume modal de 0,6(lambda/n)3. Le confinement a pu être observé par microscopie en champ proche et nous avons montré qu'il était possible de contrôler ces cavités par une pointe SNOM. . Enfin, nous nous sommes intéressés aux modes lents en abordant de façon théorique l'injection efficace de la lumière dans un mode lent

Stimulated and spontaneous four-wave mixing in silicon-on-insulator coupled photonic wire nano-cavities

We report on four-wave mixing in coupled photonic crystal nano-cavities on a silicon-on-insulator platform. Three photonic wire cavities are side-coupled to obtain three modes equally separated in energy. The structure is designed to be self-filtering, and we show that the pump is rejected by almost two orders of magnitudes. We study both the stimulated and the spontaneous four-wave mixing processes: owing to the small modal volume, we find that signal and idler photons are generated with a hundred-fold increase in efficiency as compared to silicon micro-ring resonators

Ultra-high Q/V Fabry-Perot microcavity on SOI substrate

International audienceWe experimentally demonstrate an ultra high Q/V nanocavity on SOI substrate. The design is based on modal adaptation within the cavity and allows to measure a quality factor of 58.000 for a modal volume of 0.6(λ/n)3. This record Q/V value of 105 achieved for a structure standing on a physical substrate, rather than on membrane, is in very good agreement with theoretical predictions also shown. Based on these experimental results, we show that further refinements of the cavity design could lead to Q/V ratios close to 106

Preamplified Demodulation of 56-Gb/s WDM-DPSK Signals by an AWG-Based InP PIC

A compact preamplified receiver for wavelength division multiplexed-diffferential phase shift keying (WDM-DPSK) signals based on Gaussian filtering is proposed and simulated, and a first implementation, including an semiconductor optical amplifiers (SOA) and an ad-hoc arrayed waveguide grating (AWG), is demonstrated by monolithical integration in an InP platform. The demodulation of 56-Gb/s channels on the eight 100-GHz-spaced AWG outputs is experimentally reported, and simulation results show the feasibility of multiwavelength operation obtaining simultaneous demultiplexing and demodulation of all the channels. The resilience to chromatic dispersion for the Gaussian filter demodulation is also shown by simulations

Near-field interactions between a subwavelength tip and a small-volume photonic-crystal nanocavity

International audienceThe fundamentals of the near-field interaction between a subwavelength metallic tip and a photonic-crystal nanocavity are investigated experimentally and theoretically. It is shown experimentally that the cavity resonance is tuned without any degradation by the presence of the tip and that the reported near-field interaction is strongly related to the field distribution within the nanostructure. Then, in light of a perturbation theory, we show that this interaction is selectively related to the electric field or magnetic field distribution within the cavity, depending on the tip properties

Photonics at nanometer scale: tracking light in high Q low V nanocavities

Photonic crystals (PCs) have proven to be an efficient way to tightly confine the electromagnetic field in nanocavities or slow down light propagation within optical waveguides. Very recently it has been proposed to use a nanometric optical probe to observe in near-field the light confinement and propagation within PC devices. In this work we analyze the optical properties of PC nanostructures by using a SNOM probe in collection mode in association with transmission measurements. We also explore the possibility to use the nanometric tip for a new class of Near-field Optics Nanometric Silicon Systems (NONSS) dedicated to on-chip information routing and processing. In a first step, we show that with to the SNOM probe it is possible to evidence different light behaviours depending on optical mode profile. Mode coupling in PC waveguides and quality factor changes in PC nanocavities will be discussed. Then in a second step, we show that strong field confinement enhancement can be achieved in nanocavities by proper mirror designs including mode matching and losses recycling. A quality factor (Q) enhancement by two orders of magnitude is observed. These experimental results are discussed in light of numerical calculations. Finally, in a third step, we fabricated a nanocavity in a monomode SOI ridge waveguide with an ultimately low microcavity modal volume of 0.6(l/n)^3. We use this high-Q low-V nanocavity to explore the nanocavity - nanometric optical probe interaction

Ingénierie de mode en optique intégrée sur silicium sur isolant

This thesis enters upon the localization and the handling of the light at the wavelength scale. The work initially concerned microcavities with high quality factors (Q) integrated on ridge waveguides relying on a substrate (SOI). Thanks to a mode engineering based on modes profiles adaptation, the optimization of mirrors permits us to achieve Q factors up to 60000 for a modal volume of 0,6 (lambda/n)3. Optical confinement could be observed by near-field microscopy and we showed that it was possible to control these cavities by a SNOM tip. Lastly, we investigate the slow modes approach by tackling theoretically the issue of the injection of light in slow modes.Cette thèse porte sur la localisation et la manipulation de la lumière à l'échelle de la longueur d'onde. Les travaux ont d'abord porté sur des micro-cavités à grands facteurs de qualité (Q) intégrées sur des guides rubans reposant sur un substrat (SOI). L'optimisation des miroirs grâce à une ingénierie de mode basée sur l'adaptation des profils des modes, a permis d'obtenir des Q allant jusqu'à 60000 pour un volume modal de 0,6(lambda/n)3. Le confinement a pu être observé par microscopie en champ proche et nous avons montré qu'il était possible de contrôler ces cavités par une pointe SNOM. . Enfin, nous nous sommes intéressés aux modes lents en abordant de façon théorique l'injection efficace de la lumière dans un mode lent

Ingénierie de modes en optique intégrée sur silicium sur isolant

Cette thèse porte sur la localisation et la manipulation de la lumière à l'échelle de la longueur d'onde. Les travaux ont d'abord porté sur des micro-cavités à grands facteurs de qualité (Q) intégrées sur des guides rubans reposant sur un substrat (SOI). L'optimisation des miroirs grâce à une ingénierie de mode basée sur l'adaptation des profils des modes, a permis d'obtenir des Q allant jusqu'à 60000 pour un volume modal de 0,6(lambda/n)^3. Le confinement a pu être observé par microscopie en champ proche et nous avons montré qu'il était possible de contrôler ces cavités par une pointe SNOM. Enfin, nous avons abordé la voie des modes lents en nous attaquant de façon théorique à l'injection efficace de la lumière dans un modes lents.This thesis enters upon the localization and the handling of the light at the wavelength scale. The work initially concerned microcavities with high quality factors (Q) integrated on ridge waveguides relying on a substrate (SOI). The optimization of the mirrors thanks to an engineering of mode based on the modes profiles adaptation, permits us to achieve Q factors up to 60000 for a modal volume of 0,6 (lambda/n) ^3. Confinement could be observed by near-field microscopy and we showed that it was possible to control these cavities by a SNOM tip. Lastly, we investigate the slow modes approach by tackling theoretically the issue of the injection of light in slow modes.ORSAY-PARIS 11-BU Sciences (914712101) / SudocSudocFranceF

Microring-Based Fully Integrated Silicon DQPSK Receiver

An ultra compact integrated silicon receiver for differential quadrature phase shift keying signals based on two tunable silicon-on-insulator microring resonators and four integrated germanium photodetectors is demonstrated. The device is experimentally characterized and the receiver operation is reported for signals ranging from 10 to 20 GBd