Fiber Raman amplifier

SEMICONDUCTOR OPTICAL AMPLIFIERS have received less attention in the literature than amplifiers using optical fibers as the gain medium. Fiber amplifiers, including Erbium-doped fiber amplifiers and Raman amplifiers are currently transforming the world of optical fiber telecommunications as they become incorporated as line amplifiers in high-capacity wavelength-division multiplexed (WDM) transmission systems. However, despite the dominance of fiber amplifiers in the telecommunications marketplace, semiconductor optical amplifiers continue to show potential for application in a range of... 

Currently, there are three approaches to optical amplifiers. The main approach is the rare-earth-doped fiber amplifier, EDFA being an example. The second approach is the semiconductor amplifier, which is somewhat similar to the semiconductor laser except that the end faces are made nonreflective. The third option, one that is becoming increasingly attractive, is the Raman amplifier. The fundamental mechanism for the rare-earth-doped and semiconductor amplifiers is stimulated amplification. Raman amplification on the other hand is based on a nonlinear phenomenon, stimulated Raman scattering. 

With commercially available YDFL as pumps, powers > 40 W at 1178 nm are feasible. This sets an upper limit to the conversion efficiency needed in the subsequent second harmonic generation. Numerical simulations for the amplifier and resonator Raman laser configuration indicate feasibility of the system with sufficient SBS suppression. ESO has assembled the amplifier configuration, and has demonstrated up to 4 W CW at 1178 nm. ESO s goal is to have compact and turnkey commercial fiber lasers for LGS/AO within 3 years. 

Nielsen, T.N., et al. 3 28 Tb/s 82 x 40 Gh/s) Transmission Over 3 < 300 km of Nonzero-dispersion Fiber Using Dual C- and L-band Hybrid Raman/Erbium-doped Inline Amplifiers, Optical Fiber Communication Conference, post-deadline paper 29, March 2000. 

Rare-earth-doped and Raman fiber amplifiers have gain-bandwidths of up to several tens of nanometers, enabling lasing within a wide range of wavelengths. Tuning... 

Amplification. There exists an array of optical amplifiers to increase the signal. Optical communications use fiber optic and semiconductor amplifiers. For research, there are Raman and quantum-dot amplifiers. 

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