High temperature stability 850-nm In_0.15Al_0.08Ga _0.77As/Al_0.3Ga_0.7as vertical-cavity surface-emitting laser with single Al_0.75Ga_0.25As current blocking layer

In this paper, we employed a high bandgap Al_0.75Ga _0.25As layer acting as an electronic blocking layer in the upper In_0.15Al_0.08Ga_0.77As/Al_0.3Ga _0.7As active region before the growth of p-type layers of 850-nm vertical-cavity surface-emitting lasers (VCSELs). A threshold current of 1.33mA and slope efficiency of 0.53 W/A at 25°:C were obtained, and the temperature dependent light output and voltage versus current (L-I-V) characteristics showed that the VCSELs with a high bandgap Al _0.75Ga_0.25As layer were more stable when the substrate temperature was in a range of 25-95°C. The threshold current increased with temperature up to 95°:C was less than 21% and the slope efficiency dropped only 24.5%.