Pierre Sansonetti

Design and realization of multiple quarter-wave phase-shifts UV-written bandpass filters in optical fibers

Ultraviolet (UV)-written optical fiber bandpass filters based on multiple quarter-wave phase-shifts, up to eight, are presented and modeled. It is demonstrated that the shape of the bandpass peak can be tailored by optimization of the phase-shifts locations. We show that flat top bandpass peak with negligible ripples (<0.01 dB) at the top can be designed and that a tradeoff between nearly rectangular shape and stopband width occurs when gratings containing more than two phase-shifts are to be used. We also present experimental spectral responses of gratings with up to three phase-shifts and comparisons with theoretical results.

Comparison between the finite element method, the localized function method and a novel equivalent averaged index method for modelling photonic crystal fibres

Three numerical approaches for the analysis of photonic crystal fibres are presented and compared. A full-vector finite element method based on the resolution of the Maxwell equations is found to be a very efficient and reliable tool for accurately modelling these optical guiding structures. The localized function method in the scalar form applies as long as the air-filling fraction is not too large. We present a very simplified novel model based on an equivalent averaged refractive index profile that is in good accordance with the finite element method as long as the optical wavelength is not too enlarged. Finally, comparisons between numerical results and measurements are taken into account in order to discuss the reliability of the three models.

New and efficient technique for suppressing the peaks induced, by discrete cladding mode coupling in fiber slanted Bragg grating spectrum

A new design of fiber slanted Bragg grating exhibiting a smooth transmission spectrum without the need of a specific packaging to transform the cladding modes into a continuum of radiation modes is reported.

Dependence of fiber Bragg grating thermal stability on grating fabrication process

Summary form only given. Fiber gratings thermal stability was investigated at 600/spl deg/C during 600 hours. These results point out the strong dependence of gratings thermal stability on their fabrication process, different defects may be created and different mechanisms involved, as well as the complexity of their long-term evolution law, which will have to be fully understood before deriving grating lifetime under operating conditions.

Influence of Bragg grating location in fused 100% coupler for add and drop multiplexer realization

Summary form only given. All-fiber add and drop multiplexers are key components for wavelength division multiplexing (WDM) optical transmissions. Among proposed solutions, the Mach-Zehnder interferometric structure, with two identical Bragg gratings written in both arms, is an attractive solution. We demonstrated the influence of Bragg grating location in fused fibre coupler for efficient add/drop functions.

Dispersion-managed fiber with low chromatic dispersion slope

A dispersion-balanced fiber exhibiting a low chromatic dispersion slope (<0.015 ps/nm/sup 2//km at 1550 nm) was obtained by longitudinally changing the radial dimension of a refractive index profile. We report theoretical and experimental results and trade-offs between effective-area and cable ability aspects.

Polarization mode dispersion analysis in fibre chromatic dispersion compensators

Analysis of polarization-mode dispersion in linearly chirped fiber chromatic dispersion compensators has been carried out with several types of fibers. The importance of fiber birefringence as well as fabrication process has been pointed out.

Tapered slanted Bragg grating for low insertion loss gain equalizing filter

Here is presented a solution to decrease insertion loss of slanted grating gain equalizing filter, written in fiber with specific photosensitivity profiles.

New fabrication technique of fibre Bragg gratings with arbitrary chirp and wavelength for chromatic dispersion compensation

We present here a new method allowing the fabrication of long gratings with any kind of chirp at any wavelength in a range of about 30 nm for chromatic dispersion compensation. We propose a new method, simple, cheap and versatile, allowing the realization of gratings with arbitrary chirp and wavelength using a unique phase mask with a constant periodicity. Those gratings could be then concatenated for multichanel operation.

La fibre optique : retour sur 50 ans de développement. Où en sommes-nous aujourd’hui ?

REE N°1/2015 99 CÂBLES ET INFRASTRUCTURES OPTIQUES DOSSIER 2 Introduction Apres un bref historique du deve- loppement des fibres optiques pour les telecommunications et des differents types de fibres monomodales qui y ont ete associes, cet article presente plus en detail les deux grands types de fibres utilises pour le reseau terrestre et en particulier les reseaux d’acces, le mar- che de la fibre optique monomodale et son evolution. Les technologies asso- ciees a la fabrication de la fibre optique seront decrites, ainsi que les dernieres innovations apportees par les fibres optiques insensibles a la courbure et le developpement de nouveaux types de câbles a fibres optiques et de solutions de deploiement developpees et mises en œuvre par Prysmian Group. La revolution de la fibre optique a de- marre il y a maintenant presque 50 ans, et, depuis, a permis celle de la societe de l’information. C’est en effet en 1966 que K. C. Kao et G.A. Hockham [1] pre- disent que des pertes de 20 dB/km peuvent etre obtenues dans les fibres optiques en les purifiant suffisamment, apportant un avantage decisif par rap- port aux solutions a câble coaxial ou