Caractérisation interférométrique du coefficient électro-optique de guides polymers intégrés

session affiches A7 " Instrumentation, Caractérisation et Capteurs " [A7.4]National audienceNous présentons ici une méthode de caractérisation de modulateurs électro-optiques en polymères par l'intermédiaire d'un Mach-Zehnder fibré. Les résultats obtenus par modulation de phase, dans une fibre optique soumise à des contraintes piézoélectriques, témoignent de la faisabilité de la méthode et montrent qu'une caractérisation avec une résolution satisfaisante est possible au moyen d'un procédé expérimental simple

Evidence for speed-dependent effects in NH3 self-broadened spectra: towards a new determination of the Boltzmann constant

In this paper we present an accurate analysis of the shape of an isolated rovibrational ammonia line from the strong nu2 band around 10 $\mu$m, recorded by laser absorption spectroscopy. Experimental spectra obtained under controlled temperature and pressure, are confronted to various models that take into account Dicke narrowing or speed-dependent effects. Our results show clear evidence for speed-dependent broadening and shifting, which had never been demonstrated so far in NH3. Accurate lineshape parameters of the nu2 saQ(6,3) line are obtained. Our current project aiming at measuring the Boltzmann constant, kB, by laser spectroscopy will straight away benefit from such knowledge. We anticipate that a first optical determination of kB with a competitive uncertainty of a few ppm is now reachable.Comment: 13 pages, 5 figures, 1 tabl

SOA - NOLM in Reflective Configuration for Optical Regeneration in High Bit Rate Transmission Systems

This paper presents a theoretical and experimental investigation of optical signal regeneration properties of a non-linear optical loop mirror using a semiconductor optical amplifier as the active element (SOA-NOLM). While this device has been extensively studied for optical time division demultiplexing (OTDM) and wavelength conversion applications, our proposed approach, based on a reflective configuration, has not yet been investigated, particularly in the light of signal regeneration. The impact on the transfer function shape of different parameters, like SOA position in the interferometer and SOA input optical powers, are numerically studied to appreciate the regenerative capabilities of the device.Regenerative performances in association with a dual stage of SOA to create a 3R regenerator which preserves the data polarity and the wavelength are experimentally assessed. Thanks to this complete regenerative function, a 100.000 km error free transmission has experimentally been achieved at 10 Gb/s in a recirculating loop. The evolution of Bit Error Rate for multiple pass into the regenerator and the polarization insensitivity demonstration to input data are presented

High-sensitive Optical Pulse-Shape Characterization using a Beating-Contrast-Measurement Technique

Ultrahigh-speed optical transmission technology, such as optical time domain multiplexing or optical signal processing is a key point for increasing the communication capacity. The system performances are strongly related to pulse properties. We present an original method dedicated to short pulse-shape characterization with high repetition rate using standard optical telecommunications equipments. Its principle is based on temporal measurement of the contrast produced by the beating of two delayed optical pulses in a highbandwidth photodetector. This technique returns firstly reliable informations on the pulse-shape, such as pulsewidth, shape and pedestal. Simulation and experimental results evaluate the high-sensitivity and the high-resolution of the technique allowing the measurement of pulse extinction ratio up to 20 dB with typical timing resolution of about 100 fs. The compatibility of the technique with high repetition rate pulse measurement offers an efficient tool for short pulse analysis

Etude numérique de l'impact du filtrage optique sur les propriétés régénératives d'un convertisseur de longueur d'onde interférométrique en configuration différentielle

Session affiches 19 « Systèmes et réseaux de Télécommunication » [A10.2]National audienceDans cet article, nous présentons l'étude numérique des propriétés régénératives d'un convertisseur de longueur d'onde interférométrique à base d'amplificateurs optiques à semiconducteurs, en configuration différentielle. Nous avons démontré qu'en optimisant le filtrage optique, nous pouvons améliorer la qualité du signal en sortie du convertisseur en réduisant notamment l'effet de « patterning » lié à la réponse lente de l'amplificateur optique à semiconducteurs

Caractérisation de dispositifs de récupération d'horloge tout-optique par la mesure de taux d'erreur binaire

session affiches A5 « Systèmes et Réseaux de télécommunications » [A5.2]National audienceNous proposons de caractériser différentes récupérations d'horloge tout-optiques, à base de lasers auto-pulsants à semiconducteurs, par la mesure de taux d'erreur binaire à 42,66 Gbit/s. Nous utilisons pour cela une technique de remodulation de l'horloge optique qui permet, via la mesure de taux d'erreur binaire, de comparer leurs performances et de quantifier leur sensibilité à la polarisation

Cascaded multiplexed optical link on a telecommunication network for frequency dissemination

We demonstrate a cascaded optical link for ultrastable frequency dissemination comprised of two compensated links of 150 km and a repeater station. Each link includes 114 km of Internet fiber simultaneously carrying data traffic through a dense wavelength division multiplexing technology, and passes through two routing centers of the telecommunication network. The optical reference signal is inserted in and extracted from the communication network using bidirectional optical add-drop multiplexers. The repeater station operates autonomously ensuring noise compensation on the two links and the ultra-stable signal optical regeneration. The compensated link shows a fractional frequency instability of 3 \times 10-15 at one second measurement time and 5 \times 10-20 at 20 hours. This work paves the way to a wide dissemination of ultra-stable optical clock signals between distant laboratories via the Internet network