Download or read book Amplificateur fibre double gaine codop e l erbium et l ytterbium ressource lectronique mod lisation et v rification exp rimentale written by Morasse, Bertrand and published by Université Laval. This book was released on 2006 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: Le présent projet de recherche porte sur l'étude d'un amplificateur à fibre à double gaine codopée à l'erbium et l'ytterbium de haute puissance. Le but premier du projet est de concevoir un outil de simulation capable de prédire adéquatement les performances expérimentales de tels amplificateurs en régime continu. Tout d'abord, un outil de simulation permettant de modéliser l'amplification de la lumière dans une fibre optique est développé et implémenté numériquement avec le langage de programmation C++. Ce modèle est conçu de façon générale et s'applique à tout type d'amplificateur et de laser à fibre où la structure énergétique du dopant est connue. Ensuite, la caractérisation expérimentale complète d'une fibre optique dopée est effectuée. Ces mesures sont nécessaires pour déterminer les paramètres d'entrée des simulations. Des mesures expérimentales sont également effectuées pour caractériser les performances d'un amplificateur et de lasers à fibre erbium/ytterbium.

Download or read book High gain Short length Phosphate Glass Erbium ytterbium Co doped Fiber Amplifier Working in the L band Range written by Ayman Mohammad Samara and published by . This book was released on 2002 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: EDFA (Erbium Doped Fiber Amplifier) is a mature technology and is the workhorse for all optical networks, yet its relatively large size and small band width (mainly in the C-band regime) requires further research and development efforts to achieve the ever-wanted small, compact, wide bandwidth, and efficient fiber amplifiers. In this thesis we conducted various experimental setup / configurations on a new high-gain phosphate glass Er-Yb doped fiber amplifiers. We investigated the gain characteristics of different lengths of active-fiber used in these amplifiers. Using a tunable laser, we studied the performance at different signal wavelengths and strengths (in the 1550 nm band), and influence of various pump parameters. Our results show a maximum 19 dB gain can be achieved using a 25-cm length of this active fiber, with pump power - 180 mW at 980 nm wavelength. This maximum gain is around the 1570 nm, which is in the L-band regime. The amplification bandwidth covers both C-band and L-band regimes. These results prove that a short length of this new fiber amplifier gives high gain levels that are comparable to those given by the current fiber amplifiers, and it covers a wider range of the optical communication spectra. This fiber amplifier has the potential for future mass production of very compact and efficient devices.

Download or read book L Band Bismuth Based Erbium Doped Fibre Amplifier written by Wu Yi Chong and published by LAP Lambert Academic Publishing. This book was released on 2012 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: Characterization study of Bismuth-based Erbium-doped Fibre (Bi-EDF) and its performance as gain medium for L-band Erbium-doped Fibre Amplifier (EDFA) is studied. Bismuth oxide glass host enables very high erbium doping concentration without significant concentration quenching effect. The Bi-EDF studied is only 2.15m long with Erbium ion concentration of 3,250 wt. ppm. corresponding to a maximum absorption coefficient of 157.61dB/m at 1530nm. With optimum excitation, Bi-EDFA exhibits small signal gain bandwidth of over 70nm ranging from 1550nm to 1620nm. Maximum signal gain per length coefficient at 1580nm for Bi-EDFA is 12.7dB/m. A 56nm 3dB gain bandwidth with average gain of 18.6dB is achieved. Improvement on the small signal gain performance of Bi-EDFA is demonstrated in a two-stage EDFA configuration. By utilizing C-band ASE generated by Bi-EDFA as pump source for a second stage EDF, maximum small signal gain improvement of 5.0dB over the single stage Bi-EDFA is observed.

Download or read book Two color Chirped pulse Amplification Fiber Amplifier for Mid infrared Generation written by Alaa Mohammed Al-kadry and published by . This book was released on 2010 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this thesis is developing a two-color Ytterbium (Yb) fiber amplifier system that can be used for generation of mid-infrared radiation. Previously, our group reported generating 20 [mu]W of average power, at a wavelength of 18[mu]m. This was accomplished through the amplification of a two color-seed with peaks at 1040nm and 1110nm, through a two stage amplification without any compression. The mid-infrared radiation (MIR) was generated with a 4.5 ps pulse duration by the method of difference-frequency mixing, using 300 mW of average power from the two-color Yb-fiber amplifier. Because there was no limitation by two-photon absorption, MIR output power could be scaled by increasing the amplifier power. The current project aims to increase the peak power of the laser pulses to improve the efficiency of the nonlinear mixing. The two-colour seed is generated by continuum generation in a photonic crystal fibre, pumped by 200 mW of average power from a mode-locked Yb:fibre laser. In order to efficiently increase the energy of the two wavelengths, the 4.6 mW seed pulse is now pre-amplified up to 21 mW in a 2.7 m length single mode, single core Yb:fibre . The pre-amplifier used a double-ended pumping scheme with two single mode diode lasers at 976 nm each having 150 mW maximum pump power. A notch filter was placed in the output beam to eliminate any Amplified Spontaneous Emission. After further amplification in a 7 m length of double clad, Yb-fibre, a maximum average power of 727 mW was achieved for two colours peaked at 1035 nm and 1105 nm wavelengths. The pump power for this stage was 6 W.A grating stretcher is now used to select the two-colour input along with stretching the pulses. A three grating compressor is used to compress the output pulses to 466 fs pulse duration. After compression the average power of the two colours is 350 and 110 mW for wavelengths at 1035 and 1105nm, respectively. These higher power pulses are planned to be used to increase the mid-infrared generation efficiency.

Download or read book Er yb Co doped Double Clad Fiber Amplifier Its Applications and Effects in Fiber Optic Communication Systems written by Puneit Dua and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Increased demand for larger bandwidth and longer inter-amplifiers distances translates to higher power budgets for fiber optic communication systems in order to overcome large splitting losses and achieve acceptable signal-to-noise ratios. Due to their unique design ytterbium sensitized erbium doped, double clad fiber amplifiers; offer significant increase in the output powers that can be obtained. In this thesis we investigate, a one-stage, high power erbium and ytterbium co-doped double clad fiber amplifier (DCFA) with output power of 1.4W, designed and built in our lab. Experimental demonstration and numerical simulation techniques have been used to systematically study the applications of such an amplifier and the effects of incorporating it in various fiber optic communication systems. Amplitude modulated subcarrier multiplexed (AM-SCM) CATV distribution experiment has been performed to verify the feasibility of using this amplifier in an analog/digital communication system. The applications of the amplifier as a Fabry-Perot and ring fiber laser with an all-fiber cavity, a broadband supercontinuum source and for generation of high power, short pulses at 5GHz have been experimentally demonstrated. A variety of observable nonlinear effects occur due to the high intensity of the optical powers confined in micron-sized cores of the fibers, this thesis explores in detail some of these effects caused by using the high power Er/Yb double clad fiber amplifier. A fiber optic based analog/digital CATV system experiences composite second order (CSO) distortion due to the interaction between the gain tilt—the variation of gain with wavelength, of the doped fiber amplifier and the wavelength chirp of the directly modulated semiconductor laser. Gain tilt of the Er/Yb co-doped fiber amplifier has been experimentally measured and its contribution to the CSO of the system calculated. Theoretical analysis of a wavelength division multiplexed system with closely spaced channels has been carried out to show that crosstalk can occur due to the four-wave mixing products generated inside the high power Er/Yb DCFA. A model for parametric amplification due to four-wave mixing has been developed and used to analyze its application for short pulse generation and high speed optical time division multiplexing.