Long-wavelength luminescence from In0.5Ga0.5As/GaAs quantum dots grown by migration enhanced epitaxy

We report on a systematic study of ${\mathrm{In}}_{\mathrm{0.5}}{\mathrm{Ga}}_{\mathrm{0.5}}\mathrm{As}$ quantum dots grown by the migration enhanced epitaxy technique. A maximum room-temperature luminescence wavelength of 1.37 μm has been achieved. We observe the presence of two emission maxima, which we attribute to the formation and interaction of two different dot-size distributions. Photoluminescence data analysis shows the formation of large quantum dots with good size uniformity that emit at 1.3 μm and longer due to the enhanced atomic migration lengths.