  We describe novel excitons in quantum dots by allowing for an interaction
with a Fermi sea of electrons. We argue that these excitons can be realized
very simply with self-assembled quantum dots, using the wetting layer as host
for the Fermi sea. We show that a tunnel hybridization of a charged exciton
with the Fermi sea leads to two striking effects in the optical spectra. First,
the photoluminescence lines become strongly dependent on the vertical bias.
Secondly, if the exciton spin is nonzero, the Kondo effect leads to peculiar
photoluminescence line shapes with a line width determined by the Kondo
temperature.
