100nm bandwidth flat gain Raman amplifiers pumped and gain-equalized by 12-wavelength-channel WDM high power laser diodes

Abstract

Overcoming the bandwidth limit of EDFA, one would resort to Raman amplifiers because of the possibility of much broader bandwidth by means of multiwavelength pumping scheme. We demonstrate 100nm bandwidth Raman amplifiers using 12-wavelength-channel WDM pump laser diode unit. The gain flatness is less than ±0.5dB, which is achieved through an asymmetric channel allocation of pump and without any gain equalization filters.