Monolithic integration of surface-emitting harmonic generator with InGaAs/GaAs single-quantum-well laser

We demonstrate active surface-emitting sum-frequency generators based on monolithic integration of InGaAs/GaAs single quantum well lasers and multilayer AlxGa1-xAs nonlinear waveguides. As broad area lasers with uncoated facets, threshold current densities as low as 87.5 A/cm2 have been obtained for a cavity length of 3.3 mm at 300 K. A differential internal quantum efficiency of 71% and a waveguide loss of 3.2 cm-1 have been measured from the room temperature light-current (L-I) characteristics. With an active/passive segmented cavity operating at 0.984 micrometers , coherent sum-frequency light at 0.51 micrometers was radiated from the etched-off passive segment surface when coupling 1.06 micrometers light into the cavity as the TM guided wave to interact with the TE SQW laser mode. The measured conversion efficiency in terms of the nonlinear cross section Anl is about 2 X 10-7 W-1 which agrees well with the calculated value. Potential applications of the integrated devices are briefly addressed.