GaAs 0.7 Sb 0.3 / GaAs type-II quantum well with an adjacent InAs quantum-dot stressor layer

Abstract

We report the optical properties of a composite structure comprising a type-II GaAs0.7Sb0.3/GaAs quantum well (QW) and an InAs quantum-dot (QD) layer adjacent to the QW. The low-temperature photoluminescence (PL) of the composite structure with a 5-nm-thick GaAs spacer demonstrates a redshift of 44 meV, as compared with that of GaAs0.7Sb0.3/GaAs single QW at low excitation level. The redshift reveals the existence of local potential minimums, induced by the stress exerted by the adjacent QDs, in the type-II QW. At higher temperature, the composite structure shows stronger PL intensity than the GaAs0.7Sb0.3 QW, indicating the potential of the applications to laser diodes.