Title :
Gain-clamped fiber amplifier with a short length of preamplification fiber
Author_Institution :
NTT Labs., Kanagawa, Japan
Abstract :
Although gain-clamping an erbium-doped fiber amplifier (EDFA) by a counterpropagating ring resonator prevents oscillation light from being output, it degrades the amplifier´s noise figure. The noise figure degradation can be reduced by using a length of EDF, that is short enough not to cause any gain saturation, for preamplification. Experiments confirm that the prestage EDFA reduces the noise figure degradation under constant gain operation.
Keywords :
erbium; laser beams; laser cavity resonators; laser feedback; laser noise; optical fibre amplifiers; optical transmitters; ring lasers; wavelength division multiplexing; Er-doped fiber amplifier; constant gain operation; counterpropagating ring resonator; gain saturation; gain-clamped fiber amplifier; gain-clamping; noise figure; noise figure degradation; oscillation light; preamplification; preamplification fiber; Degradation; Erbium-doped fiber amplifier; Noise figure; Optical amplifiers; Optical feedback; Optical fiber amplifiers; Optical fibers; Optical ring resonators; Preamplifiers; Wavelength division multiplexing;
Journal_Title :
Photonics Technology Letters, IEEE
