Single contact monolithically integrated DFB laser amplifier

A monolithic 1550-nm single-mode AlInGaAs-InP multiple quantum-well distributed feedback laser and amplifier is presented. For the 400-μm-long grating section /spl kappa/=112+ 30i cm/sup -1/, while the output is taken from the 200-μm-long amplifier section. The slope efficiency of the chip was 0.21 W/A, while the kink free power from the fiber was 34 mW. Narrow linewidths of <50 kHz were measured, and the dispersion penalty remained less than 2.0 dB for a data rate of 2.5 Gb/s over 300 km of SMF-28.