Interface properties of InAs quantum dots produced by antimony surfactant-mediated growth: Etching of segregated antimony and its impact on the photoluminescence and lasing characteristics

We present a method that improves the emission efficiency of InAs quantum dots (QDs) fabricated by antimony surfactant-mediated metal organic chemical vapor deposition. This process consists of removing the excess segregated antimony from the surface of InAs/Sb:GaAs QDs by applying a high arsenic pressure before capping. In such a way, one benefits from the advantages of InAs/Sb:GaAs QDs (high density, low coalescence) without the formation of antimony-induced nonradiative defects. Finally, we show that this better QD interface quality results in a strong decrease of the threshold current densities of InAs/Sb:GaAs QD lasers in the 1.3 mu m band.