610-nm band AlGaInP single quantum well laser diode

The short-wavelength limits of AlGaInP visible laser diodes with Al_0.5In_0.5P cladding layers, and Ga_xIn _1-xP single quantum well (QW) active regions are investigated. Good performance is maintained throughout the 620 nm band, but the characteristics rapidly degrade in the 610 nm band. Biaxial-compression and -tension were compared, with the case of tension yielding slightly better performance. Using a 25 Å Ga_0.45 In_0.55P QW, a wavelength of 614 nm was obtained, while a 50 Å Ga_0.6In_0.4P QW emitted at 620 nm with a threshold current density of 0.8 kA/cm². These results with thin single QWs indicate the effectiveness of using an Al_0.5In_0.5P cladding layer to reduce electron leakage