Photoluminescence studies of GaSbBi quantum dots grown on GaAs by liquid phase epitaxy

Liquid phase epitaxial growth from a saturated GaSb solution in Ga with 1.3 at.% Bi, on GaAs substrates is shown to produce quantum dots with a Bi content of 0.5 at.%. The height and dimensions of the QDs are investigated by field effect scanning electron microscopy and atomic force microscopy. The density of the small QDs is approximately 4.3 × 109cm−2, with dimensions in the range of 20-100 nm and height of ∼10 nm. Theoretical calculations reveal that the QDs have band alignment structure of type-II as predicted from GaSbBi bulk band structure. The 12 K photoluminescence (PL) of the QDs shows broad emission band in the range 1.25-1.37 eV. Gaussian deconvolution is used to resolve the broad peak into three individual PL emission peaks which are thoroughly explored by their dependence on temperature and excitation power.