A short-period GaAs-AlGaAs quantum-wire array laser with a submicrometer current blocking layer

The structure and device characteristics of a 700-nm-pitch GaAs-AlGaAs quantum-wire array laser (QWAL) with a dielectric defined current blocking layer are reported. The high wire density of the QWAL has been expected to yield more efficient carrier capture, but large spacing between the quantum wires was found to deteriorate the laser characteristics. We have improved electrical confinement into the active regions by incorporating a SiO₂ film onto the large spacing. Room-temperature pulsed operation with an output power of 9 mW at 191-mA injection current was achieved for a 200×500 μm laser with uncoated facet. The threshold current density was 0.14 kA/cm². The dependence of the threshold current and the maximum power on the cavity length and width was also studied.