InGaAs/InAsPSb diode lasers with output wavelengths at 2.52 μm

We have studied InGaAs/InAsPSb double heterojunction, oxide stripe lasers grown by hydride vapor phase epitaxy. At 80 K the threshold current density is 0.4 kA/cm2, the staturated output power is about 4 mW, and the differential quantum efficiency just above threshold is 20% per facet. The output wavelength increases from 2.44 μm at 80 K to 2.52 μm at 190 K. A layer of compositionally graded InGaAs accommodates the 2% lattice mismatch between the InP substrate and the laser structure. The operating characteristics of these lasers are compared with those of InGaAs/InAsP lasers. Their improved performance results from the better electrical and optical confinement of the InAsPSb cladding layers.