Low growth rate InAs/GaAs quantum dots for room-temperature luminescence over 1.3 μm

Abstract

Uncapped InAs/GaAs quantum dots with average height around 15 nm were grown under the regime of ultra-low growth rates (<0.01ML/s). When GaAs capped, such structures exhibited room-temperature luminescence in the 1.1–1.4 μm range. The effect of phonon bottleneck was not observed and the presence of multiple peaks in the photoluminescence spectra was caused by state filling, as observed in measurements as a function of the excitation-power density. A carrier dynamics that involved thermal emission of carriers into the GaAs barrier and recapture by the quantum dots was observed when the optical emissions were monitored at different temperatures.