Growth and optical investigation of strain-induced AlGaAs/GaAs quantum dots using self-organized GaSb islands as a stressor

The strain-induced quantum dots in a two-dimensional AlGaAs/GaAs quantum well plane are first reported to be fabricated by using self-organized GaSb islands as a stressor, which is confirmed by magnetophotoluminescence measurement. In the photoluminescence spectra, the emission peaks from this quantum dots and undisturbed quantum well are observed. In addition, the energy separation between these two peaks increases with the decrease of the thickness between the self-organized GaSb island and quantum well plane. When this thickness is 12.5 nm, the energy separation between these two peaks is about 21 meV. The calculation based on the strain distribution and parabolic potential model gives a good agreement with photoluminescence results. Furthermore, the optimum size of the self-organized GaSb islands as a stressor on the GaAs surface is about 36 nm.