Lateral coupling - a material independent way to complex coupled DFB lasers

We have developed a new technique for the fabrication of complex coupled di stributed feedback laser (DFB) lasers. A metal grating patterned lateral to a narrow ridge waveguide laser couples to the evanescent part of the guide d mode. No regrowth is required for the processing, which makes this approa ch applicable to all material systems. DFB lasers fabricated from InGaAs/Al GaAs quantum well and dot lasers, GaTnNAs DFB lasers emitting at 1.3 mum an d long wavelength lasers at 2 mum based on InGaSbAs/AlGaSbAs structures are described. The lasers show low thresholds, good efficiencies and a high si demode suppression ratio. (C) 2001 Elsevier Science B.V. All rights reserve d.