Dense lying GaSb quantum dots on GaAs by Stranski-Krastanov growth

GaSb quantum dots (QDs) have been grown epitaxially on GaAs in the Stranski-Krastanov (SK) mode. By variation of the Sb/Ga-V/III flux ratio, the growth temperature, and the nominal coverage the QD dimensions and optoelectronic characteristics can be tuned. These modifications enable dense lying dots with a density up to 9.8 x 10 10 cm -2 . The position of the photoluminescence (PL) peak can be varied between 0.850 and 1.378 μm by precise control of growth parameters. To raise the PL intensity and QD laser output power samples with a stack of GaSb QD layers are grown on GaAs wafer. A GaSb-QD-laser with a 8-fold stack and an emission wavelength around 0.900 μm is realized with a differential quantum efficiency of 54%.