Vol. 58 n°9-10, September-October 2003
Optical communications (1) Advanced technologies for photonics
Guest editors Yves JAOUËN* and Michel JOINDOT**
*GET/Télécom Paris
**France Télécom R&D
System Simulation: a tool to validate the insertion of optoelectronic devices into a 40 Gbit/s fiber-optic link
Christelle AUPETIT-BERTHELEMOT*, Anne DUBOIS**, Jean-Louis VERNEUIL*, Jean-Michel DUMAS*
* Université de Limoges - Ecole Nationale Supérieure d'Ingénieurs de Limoges , Groupe d'Étude des systèmes de Télécommunications de l'ENSIL, 16, Rue Atlantis - Parc Ester - BP 6804- 87068 Limoges cedex, France
** Université Pierre et Marie Curie - Laboratoire de Génie Électrique de Paris - Supelec - Plateau de Moulon, rue Joliot Curie - 91192 Gif sur Yvette Cedex, France.
Abstract: The main objective of this contribution is the optimization of a 40 Gbit/s fiber-optic link by means of a system simulator. In a first step, the link is developed on the basis of the models issued from the library of the selected simulator. These models are too simple. In a second step, the models have been improved taking into account measurements carried out in our laboratory or supplied by industrial partners. New models are also implemented. Thus, we defined a realistic simulated link which validates the insertion into systems of micro-optoelectronic devices. The quality factor (Q), bit error rate (BER) and eye pattern of the overall link are the simulated system parameters taken into account to estimate the quality of the 40 Gbit/s transmission.
Key words: Optical telecommunication, Optoelectronic device, Optical fiber transmission, System simulation, Quality factor, Error rate, Eye pattern, Modeling.
Fast liquid crystal end-less polarisation controller for first order PMD compensation
Laurent DUPONT*, Jean-Louis de BOUGRENET de la TOCNAYE*, Michel GADONNA*, Thierry SANSONI*
* GET/ENST Bretagne Département d'Optique, Technopôle de Brest-Iroise, BP 832, 29280 Brest Cedex, France
Abstract: We present the principle of a fast liquid crystal end-less polarisation controller for first order polarisation mode dispersion compensation (PMD). We demonstrate how this device can be used as a variable and rotatable wave-plate and the resulting advantages to optimize the complexity of polarisation tracking algorithms. We give some experimental results obtained with an electro-clinic homeotropically aligned liquid crystal cell used as a variable and rotatable wave-plate. We discuss then the performance and the way to improve the device characteristics in order to meet the current operational PMD compensation requirements.
Key words: Optical fiber transmission, Wave dispersion, Light dispersion, Wave polarization, Optical polarization, Signal convertor, Liquid crystal device.
Investigations of the fundamental quantum noise properties of resonant-cavity light-emitting diodes (RCLEDs)
Philipp KAPPE*, Joachim KAISER*,Wolfgang ELSÄSSER*, Ralph WIRTH**, Klaus STREUBEL**
* Institute for Applied Physics, Darmstadt University of Technology, Schloßgartenstr. 7, 64289 Darmstadt, Germany.
** OSRAM Opto Semiconductors, Wernerwerkstr. 2, 93049 Regensburg, Germany.
Abstract: We present first results of the investigations of the quantum noise properties of resonantcavity light-emitting diodes (RCLEDs). We obtain a quantum noise of up to -0.07dB below the shot noise quantum limit already at moderate pump levels and when being pumped by a quiet current source. This amount of observed sub-shot noise emission is in accordance with the quantum efficiency of the devices. This Sub-Poisson intensity noise of RCLEDs together with their narrow beam characteristics make them very attractive for applications in photonics and metrology.
Key words: Light-emitting diode, Cavity resonator, Quantum noise, Quantum effect.
Liquid crystal-based optical space switches for DWDM networks
Philippe GRAVEY*, Jean-Louis de BOUGRENET de la TOCNAYE*, Bruno FRACASSO*, Nicole WOLFFER*, Antoine TAN*, Bruno VINOUZE*, Mustapha RAZZAK*, Amal KALI*
* GET/ENST Bretagne, Département d'Optique, Technopôle de Brest-Iroise, BP 832, 29285 Brest CEDEX, France.
Abstract: This paper addresses the issue of using conventional liquid crystal materials as reconfigurable holographic or diffractive phase elements within optical space switches and the resulting constraints in their choice and use in a telecommunication environment. We discuss the advantage of this technology for implementing holographic-based approaches with respect to other techniques. As an illustration we give two examples which illustrate two generic architectures and complementary use of liquid crystal to implement them. Finally, we give some trends on implementations of high channel capacity space switches based on this technology.
Key words: Optical switch, Space division switching, Liquid cristal device,Wavelength division multiplexing, Nematic, Smectic, Phase modulation, Blazed grating, Optical modulator, Holography.
Novel applications of fiber Bragg grating components for next-generation WDM systems
Martin GUY*, François TRÉPANIER*, Aidan DOYLE*, Yves PAINCHAUD*, Richard L. LACHANCE*
* TeraXion Inc., 20-360 Franquet, Sainte-Foy, Québec, Canada, G1P 4N3
Abstract: The main purpose of this paper is to present an overview of novel applications enabled by major improvements realized in FBG technology. First, we will review the principle of operation of FBG-based components and the numerous recording techniques used to fabricate those types of components. We will next show that this technology combined with new innovative manufacturing process is well suited to overcome the challenges imposed on optical components for next-generation WDM systems.
Key words: Optical telecommunication, Optical fiber transmission, Wavelength division multiplexing, Distributed Bragg reflection, Optical amplifier, Equalization, Frequency filtering, Optical filter, Wave dispersion, Light dispersion, Compensator.
Photonic crystals and the real world of optical telecommunications
Jean-Michel LOURTIOZ*, Henri BENISTY**, Alexei CHELNOKOV*, Sylvain DAVID*, Ségolène OLIVIER***
* Institut d'Électronique Fondamentale, UMR 8622 du CNRS, Université Paris-Sud, Bât. 220, 91405, Orsay Cedex (France)
** now at Laboratoire Charles Fabry de l'Institut d'Optique, UMR 8501 du CNRS, 91403 Orsay cedex, (France)
*** Laboratoire de Physique de la Matière Condensée, UMR 7643 du CNRS, École Polytechnique, 91128 Palaiseau cedex, (France)
Abstract: The last decade has seen a tremendous interest in the field of photonic crystals. After a review of the basic properties of ideal two-dimensional photonic crystals, we describe the recent advances that lead to consider them as good candidates for a powerful control of light in future miniature photonic devices. The choice of devices is oriented in view of possible applications to high-density telecommunication optical circuits. We first mainly focus on integrated optics with 2D photonic crystals that are the most fascinating in terms of miniaturisation with existing technologies. We discuss the critical issues for minimising the propagation losses in photonic-crystal waveguides as well as the interest of high-Q cavities and the last advances in building-blocks for ultra-compact photonic integrated circuits. We also show the recent advances in microstructured fibres, that are certainly promised to be the most immediate application of photonic crystals in the real world of optical communications. Finally, we present new technologies and architectures that open the way to threedimensional structures with the ultimate goal of a full control of light. This is followed by conclusive remarks on what photonic crystals can bring to the field of telecommunications.
Key words: Artificial dielectric, Photonic crystal, Two-dimensional system, Review, Optoelectronics, Periodic structure, Optical waveguide, Planar technology, Optical component, Passive component, Active component, Optical fiber, Silicon, Three-dimensional system, State of the art, Telecommunication application.
New devices for microwave photonics in optical communications
Christophe MINOT*
* GET/Télécom Paris, 46 rue Barrault, 75634 Paris Cedex 13,
Abstract: Optical microwave interactions in photonic devices are reviewed in the perspective of applications to optical communication systems. Laser sources, light modulators and photodetectors are successively considered, with emphasis on basic concepts of microwave photonics and their recent developments in new, faster and more efficient devices. The main advances concern dual-mode lasers, as well as modulators and photodetectors in the traveling- wave configuration.
Key words: Optical telecommunication, Optical fiber transmission, Optoelectronic device, Millimetric wave,
Hybrid system, Access network, Wave dispersion, Optical modulation, Laser, Distributed Bragg, reflection laser, Optical modulator, Mach Zehnder interferometer, Photodetector.
Microstructured air-silica fibres: recent developments in modelling, manufacturing and experiment
Dominique PAGNOUX*, Ambre PEYRILLOUX*, Philippe ROY*, Sébastien FEVRIER*, Laurent LABONTE*, Stéphane HILAIRE*
* Institut de Recherche en Communications Optiques et Microondes - Unité Mixte de Recherche n° 6615, Faculté des Sciences et Techniques, 123, Avenue Albert Thomas F-87060 LIMOGES CEDEX.
Abstract: The main modelling methods devoted to microstructured air-silica optical fibres (MOFs) are presented and discussed. Then, the specific propagation properties of MOFs are studied in detail. Characteristics measured on fibres manufactured in our laboratory or reported in the literature are analysed. A large number of potential and demonstrated applications are presented and the obtained performances are discussed. A particular attention is given to hollow- core photonic bandgap fibres and their applications.
Key words: Optical fiber, Compound structure, Photonic crystal, Periodic structure, Modeling, Optical fiber cladding, Manufacturing, Optical properties, Transmission characteristic, Optical component.
Fiber optic applications of multiple quantum well electroabsorption modulators
Abderrahim RAMDANE*, Fabrice DEVAUX**, Nayla EL DAHDAH*, Guy AUBIN*
* CNRS/Laboratoire de Photonique et de Nanostructures, Route de Nozay, 91 460, Marcoussis, France.
** Opto+, Alcatel R&I, Route de Nozay, 91460 Marcoussis, France.
Abstract: Electroabsorption modulators (EAM) have proved to be very attractive both as optical sources (monolithically integrated NRZ transmitters and RZ pulse generators) as well as for very fast signal processing (demultiplexing, regeneration, wavelength conversion,...). Their design criteria, technology and implementation in future networks are reviewed, and the main issues are discussed.
Key words: Optical modulator, Electroabsorption, Multiple quantum well, Optical fiber transmission, Telecommunication application, Electrooptical effect, High rate, Optical source, Integration, Ultrashort pulse, Signal processing.
A key component in optical systems: the silica-based Arrayed Waveguide Grating (de)multiplexer. Overview and perspectives
Arnaud RIGNY*
* Avanex France, Route de Villéjust, 91625 Nozay, Cedex, France.
Abstract: In the ten past years, the telecommunication industry has experienced an unprecedented growth rate. To follow the exponential Bandwidth demand, new transmission technologies have emerged. Amongst them, we find Wavelength Division Multiplexing (WDM) technology. Its appearance coinciding with the emergence of key optical functions. This paper addresses one of these key optical functions, today an absolute must: wavelength demultiplexing. This function can be realized thanks to a demultiplexer, also named AWG, the acronym for Arrayed Waveguide Gratings. It took only ten years to transform the first research experiments into real commercial products: demultiplexers using a silica on silicon planar platform. This platform allowed yesterday the realization of demultiplexer AWG-products, managing high channels count at a relatively low cost, today this same platform allows the integration of complex optical functions with a more drastic cost reduction. As for tomorrow, transmission systems will continue to require new signal processing functions to permit high bit rate transmission. Once again, the AWG can play a key role.
Key words: Optical telecommunication,Wavelength multiplexing, Multiplexer, Demultiplexer, Planar technology, Optical waveguide, System design, Transmission characteristic, Commercial product, Optical component, State of the art.
40 Gbit/s transmission: III-V Integrated Circuits for opto-electronic interfaces
André SCAVENNEC*, Jean GODIN*, René LEFEVRE*
* Alcatel R&I, Opto+Route de Nozay, F-91461, Marcoussis.
Abstract: Increasing both wavelength count and bit rate per channel is presently implemented in order to improve the use of optical fiber bandwidth. This calls for suitable device structures and technologies for both optoelectronic transducers and associated driving electronics. For transmission at 40 Gbit/s per channel, Si and III-V microelectronic technologies are presently investigated with first successful demonstrations. In this paper the potential of GaAs and InP-based technologies to answer the 40 Gbit/s requirements and expected subsequent evolutions is addressed.
Key words: Optical fiber transmission, Optoelectronic device, Integrated circuit, III-V compound, High rate, State of the art, Two-dimensional electron gas transistor, Gallium arsenide, Indium phosphide.
MOEMS devices and their applications to optical telecommunication systems
Michel de LABACHELERIE*, Julien THEVENET*
* Laboratoire de Physique et Métrologie des Oscillateurs ; 32 av. de l'Observatoire - 25044 Besançon Cedex, France
Abstract : This paper describes first the basic MOEMS technologies and attempts to point out the various degrees of freedom that are available for the designer. Then, it will review some of the most important architectures of MOEMS demonstrated up to now, for optical switching and wavelength management in WDM networks. These technologies are also very promising for optical connectorization, and could open the way to new components that could be cheap enough for being used at the subscriber level. An analysis of the present status of MOEMS technologies, the main short term issues, and some development prospects will finally be given.
Key words: Microstructure, Micromechanics, Optoelectronics, Microelectronic fabrication, Actuator, Mirror, Optical switch, Wavelength division multiplexing, Frequency filtering, Optical modulator, Optical component, Packaging, Connectics, State of the art.
Raman fiber lasers for optical communication application
Jean-Christophe BOUTEILLER*
* OFS Laboratories, 25 Schoolhouse Rd, Somerset, NJ 08873, USA, jean-christophe.bouteiller@m4x.org
Abstract: We review the principle and characteristics of cascaded Raman fiber lasers in their telecommunication applications. The fundamentals of Raman fiber lasers are described, such as pumping scheme, fiber type and reflectors. We explain simple equations for CW laser operation as well as a possible way to calculate spectral width. We investigate the common issues in the use of Raman fiber lasers : theoretical optimization, control of the linewidth, suppression level of the other Stokes orders and relative intensity noise. Finally the more complex multiple-wavelength Raman fiber lasers are reviewed.
Key words: Optical telecommunication, Laser, Optical fiber, Raman process, Stimulated Raman Scattering, Bragg reflection, Non linear optics, Multifrequency operation.
