Temperature Dependent Quenching Mechanisms of the Luminescence of InGaAs/GaAs Strained Quantum Wells

Abstract

ABSTRACTIn this work we report on detailed temperature dependent photoluminescence measures on InGaAs/GaAs strained layer quantum well structures. Excitation energies above and below the GaAs band gap have been used in order to separate the contributions of the carrier trapping to the generation-recombination processes from the recombination mechanisms proper of the quantum wells. The results show that a decrease of the trapping efficiency contributes to the photoluminescence quenching, and suggest that the strong photoluminescence quenching observed in these structures should be mainly attributed to defects present in the quantum wells. A clear dependence of the luminescence quenching on the excitation intensity has also been found.