155-μm distributed feedback laser monolithically integrated with amplifier array

Abstract

We present a laterally coupled 1.55-μm distributed feedback laser monolithically integrated with multistage multimode interferences and semiconductor optical amplifiers, using low-bias currents and providing an output power of ∼100 mW with a quasi-single spatial-mode far-field pattern and low divergence angle of 3.5° in the horizontal direction. The fabrication techniques are based on side-wall gratings and quantum-well intermixing and offer a simple, flexible, and low cost alternative to conventional methods.