Photoluminescence spectroscopy of trions in quantum dots: A theoretical description

We present a full configuration-interaction study of the spontaneous recombination of neutral and singly charged excitons (trions) in semiconductor quantum dots from weak- to strong-coupling regimes. We find that the enhancement of the recombination rate of neutral excitons with increasing dot size is suppressed for negative trions and even reversed for positive trions. Our findings agree with recent comprehensive photoluminescence experiments in self-assembled quantum dots [ P. Dalgarno et al. Phys. Rev. B 77 245311 (2008)] and confirm the major role played by correlations in the valence band. The effect of the temperature on the photoluminescence spectrum and that of the ratio between the electron and hole wave-function length scales are also described.