Download or read book Raman Lasers and Amplifiers in GeO[subscript]2 Doped Optical Fibers written by Kamran Ahmad and published by . This book was released on 2004 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: The importance of Raman gain in optical fibers and its applications in communication systems have been well recognized since early 1970's. Due to broad stimulated gain bandwidths, Raman amplifiers and tunable lasers have become excellent devices for long haul and broadband optical communication networks. In this thesis we demonstrate the construction of cost effective and efficient ring Raman lasers. The ring lasers are constructed using wavelength division multiplexing (WDM) couplers and a variety of germano-silicate (GeO[subscript]2/SiO[subscript]2) fibers namely Corning SMF-28, HI-1060, and HI-980. We also demonstrate a compound ring Raman laser in SMF-28 fiber with double WDM couplers connected in parallel that generates up to 6th order cascaded Stokes, operating near 1572nm, using a Yb-doped fiber laser pump at 1117nm. The output power of this laser is 0.65W for an input power of 4.2W and hence a conversion efficiency of 15%. Another compound ring Raman laser in HI-1060 with double WDM couplers in series configuration has been demonstrated which generates up to 4th order Stokes near 1350nm, with the same input power. The comparison of the experimental results obtained from both single-coupler and double-coupler ring Raman lasers along with a possible explanation for the results using relevant theory have been presented. A Raman fiber amplifier has also been demonstrated in which gain is provided by transmission fiber itself. Using a pump of 700mW power at 1480nm wavelength, a gain of l6dB has been obtained near 1584nm. In order to obtain uniform gain over a broad band, a distributed Raman amplification (DRA) technique has been used. The gain flattening over a wideband is achieved using multi-[lambda] pumping. Simulation results show that about I0dB gain can be achieved in a %7E50nm band at wavelengths ranging from 1560-1610nm using 6-[lambda] pump in 1460-1510nm range.