High-power diode lasers based on InGaAsP spacer and waveguide layers with AlGaAs cladding layers

摘要

Abstract: Broad-area stripe laser diodes based on GaAs and Al-free spacer and Al-free spacer and waveguide layers were studied and compared to conventional AlGaAs-laser diodes. The structures were grown by low pressure MOVPE (metal organic vapor phase epitaxy). For the active region InGaAs-single quantum wells with an emission wavelength of 915 nm were used. Threshold current density, internal loss and internal efficiency are comparable for the three structures under study. The use of a quaternary spacer layer instead of GaAs improves the performance for laser diodes with a low divergence ($Theta$-perpendicular$/ $EQ 20$DGR FWHM). Using a non-optimized facet coating procedure about 1.2 W cw output power at a vertical divergence of $Theta$-perpendicular$/ $EQ 26.5$DGR are obtained from a 50 $mu@m wide stripe laser with Al-free waveguides.!18