Relaxation pathways in InAs/GaAs quantum dots

We have investigated individual InAs quantum dots in GaAs using photoluminescence spectroscopy. The dots were grown by the Stranski-Krastanov technique. We find that holes in excited states sometimes recombine with electrons in the ground state. Using power-dependent spectroscopy in conjunction with a rate-equation system to model the intensity behavior, we find that the presence of holes in excited states is also observable when monitoring the photoluminescence between electrons and holes in their single-particle ground states.