John Zyskind

John Zyskind is vice president of engineering for Lightwave Logic (Englewood, CO).

(All figures courtesy of Oclaro and NEL America)
FIGURE 1. In a hybrid Raman/EDFA system, the high-power 14xx nm Raman pump diodes are combined and launched into the fiber span counter-propagating with respect to the signal. Distributed Raman preamplification provides low noise, and the EDFA section provides high gain and high output-signal power. Flat gain spectra over a wide range of gains are provided by the combination of the four-pump-wavelength Raman pump configuration and the two-stage EDFA with variable optical attenuator and gain-flattening filter between the two stages.
Fiber Optics

PHOTONICS APPLIED: COMMUNICATIONS: Optical amplifiers increase communications network reach

Dec. 1, 2011
C- and L-band erbium-doped fiber amplifiers, hybrid Raman/EDFA systems, new gain-medium materials, and semiconductor optical amplifiers continue to extend the reach of wavelength...