INGAAS/GAAS SINGLE-QUANTUM-WELL LASERS WITH MONOLITHICALLY INTEGRATED MULTILAYER WAVE-GUIDES FOR SURFACE-EMITTED SUM-FREQUENCY GENERATION

We report on strained layer InGaAs/GaAs single quantum well (SQW) lasers with monolithically integrated nonlinear wave guides for surface-emitting sum-frequency generation. Broad-area, ridge wave-guide and segmented cavity lasers with uncoated facets were processed from a molecular beam epitaxy grown AlxGa1-xAs multilayer embedded with an InGaAs SQW separate cofinement heterostructure and tested at room temperature. Broad-area threshold current density of 87.5 A cm-2 was obtained for a cavity length of 3.3 mm and ridge lasers had a minimum threshold current of approximately 8 mA. The differential internal quantum efficiency, wave-guide loss, and lasing wavelength variation with cavity length were investigated. The sum-frequency generation (SFG) was studied in an active/passive segmented cavity device by coupling 1.06 mum light into the cavity as the transverse magnetic guided wave to interact with the transverse electric SQW laser mode. The measured conversion efficiency in terms of the nonlinear cross section A(nl) is about 2 x 10(-7) W-1, which agrees well with the calculated value. Applications of the integrated devices as WDM demultiplexers and spatially addressable coherent detectors were demonstrated.