Excitonic states in In(Ga)As self-assembled quantum dots

We have studied the excitonic absorption of single In(Ga)As self-assembled quantum dots by photoluminenscence excitation spectroscopy. We find that the absorption spectrum varies drastically with the symmetry of the dot structures: the lower the symmetry is, the more complicated is the structure of the excitonic absorption. For dots of high symmetry we demonstrate that the mixing of quantum configurations by two-body interactions in the electron-hole complex leads to distinct absorption spectra controlled by the number of confined electronic shells.