CHARACTERIZATION OF AN INGAAS-GAAS-ALGAAS STRAINED-LAYER DISTRIBUTED-FEEDBACK RIDGE-WAVE-GUIDE QUANTUM-WELL HETEROSTRUCTURE LASER

InGaAs-GaAs-AlGaAs strained-layer DFB ridge-waveguide lasers requiring a single MOCVD growth step are shown to operate in a single longitudi nal mode up to 2.2 x I(th) with an AR coating applied to one facet und er room temperature, pulsed conditions. A value of kappa-L = 0.33 has been determined from threshold gain calculations for coated and uncoat ed devices. Weak lateral optical confinement, provided by unpumped lat eral gratings, is demonstrated by the absence of antiguiding effects, and a real lateral index step of approximately 4 x 10(-3) is determine d from near-field emission patterns.