Title :
Demonstration of optical noise reduction using nonlinear absorption in a semiconductor laser amplifier
Author :
Tsurusawa, Munefumi ; Usami, Masashi ; Matsushima, Yuichi
Author_Institution :
KDD Kamifukuoka R&D Labs., Saitama, Japan
Abstract :
We propose a new way to use a semiconductor laser amplifier driven under a loss condition for a signal light that acts as an ultrafast noise reduction device using a nonlinear absorption effect. The absorption recovery time was reduced by stimulated recombination due to continuous-wave additional light (assist light) whose wavelength was longer than that of the signal. This simple method is an attractive technique to realize optical functional devices with an ultrahigh-repetition rate. We have successfully confirmed a receiver sensitivity improvement of 0.5 dB in a 5-Gb/s nonreturn-to-zero signal by using this principle. The improvement of the eye opening by passing through the noise reduction device was estimated theoretically to reveal design rules for an optimum optical noise reduction device
Keywords :
high-speed optical techniques; laser noise; optical losses; optical receivers; optical saturable absorption; quantum well lasers; semiconductor device noise; semiconductor optical amplifiers; 5 Gbit/s; InGaAsP-InGaAs; MQW active layer; SLA; absorption recovery time; assist light; continuous-wave additional light; design rules; eye opening; loss condition; nonlinear absorption; nonreturn-to-zero signal; optical functional devices; optical noise reduction; receiver sensitivity improvement; semiconductor laser amplifier; signal light; stimulated recombination; ultrafast noise reduction device; ultrahigh-repetition rate; Absorption; Laser noise; Noise reduction; Optical devices; Optical losses; Optical noise; Optical receivers; Radiative recombination; Semiconductor lasers; Semiconductor optical amplifiers;
Journal_Title :
Selected Topics in Quantum Electronics, IEEE Journal of
DOI :
10.1109/2944.788460
