Photoluminescence linewidth narrowing of InAs/GaAs self-assembled quantum dots

The effects of desorption and diffusion of indium adatoms on the photoluminescence (PL) from InAs self-assembled quantum dots (QDs) are investigated by introducing growth interruptions after QD formation. Large, low-density and small, high-density QDs were grown by molecular beam epitaxy using low View the MathML source and high View the MathML source growth rates, respectively. The PL from the QDs grown at View the MathML source and with various growth interruption times exhibit decreasing linewidths from 40 to View the MathML source with increasing growth interruption time up to View the MathML source. The narrowing of the PL linewidth results from improved size homogeneity due to desorption and diffusion of adatoms from small View the MathML source InAs clusters. The narrowing of the PL linewidth from the InAs dots is combined with low-temperature GaAs capping to obtain a linewidth of View the MathML source.