Carrier thermodynamics in InAs/InxGa1-xAs quantum dots

We present a detailed study of the carrier thermodynamics in InAs/InxGa1-xAs self-assembled quantum dots performed via an accurate determination of the dependence of the quantum dot photoluminescence efficiency on temperature, excitation power density and wavelength. We have found experimental evidences that the electron and hole populations in the dots are highly correlated. We also show that other puzzling effects, like the onset of the superlinear dependence of the quantum dot integrated photoluminescence intensity on the excitation power density, stem from the saturation, by the photogenerated carriers, of nonradiative centers in barrier.