  We demonstrate charge tuning in strain free GaAs/AlGaAs quantum dots (QDs)
grown by droplet epitaxy on a GaAs(111)A substrate. Application of a bias
voltage allows the controlled charging of the QDs from $-3|e|$ to $+2|e|$. The
resulting changes in QD emission energy and exciton fine-structure are recorded
in micro-photoluminescence experiments at T=4K. We uncover the existence of
excited valence and conduction states, in addition to the s-shell-like ground
state. We record a second series of emission lines about 25meV above the
charged exciton emission coming from excited charged excitons. For these
excited interband transitions a negative diamagnetic shift of large amplitude
is uncovered in longitudinal magnetic fields.
