Room-temperature pseudomorphic InxGa1−xAs/GaAs quantum well surface-emitting lasers at 0.94–1.0 μm wavelengths

Abstract

We report room-temperature lasing at 0.94–1.002 μm in high-finesse Fabry– Perot resonators with Inx Ga1−x As/GaAs multiple quantum well active layers (x=0.18–0.2). The quantum wells and AlAs/GaAs quarter-wave stack mirrors were epitaxially grown on GaAs substrates. Optically pumping with 0.875 μm, 10 ps pulses yielded a threshold of 15 pJ incident pulse energy. The equivalent threshold current density is about 26 μA/μm2 (2.6 kA/cm2 ), suggesting ultralow thresholds in micrometer-size devices. At the lasing wavelengths the GaAs substrates are essentially transparent allowing the possibility of integrating micro-optic lenslets on the substrate backsides for light collection. Nonlinear optical gating of 1.064 μm light was also achieved in these structures.