Optical control of energy-level structure of few electrons in   AlGaAs/GaAs quantum dots
  Optical control of the lateral quantum confinement and number of electrons confined in nanofabricated GaAs/AlGaAs quantum dots is achieved by illumination with a weak laser beam that is absorbed in the AlGaAs barrier. Precise tuning of energy-level structure and electron population is demonstrated by monitoring the low-lying transitions of the electrons from the lowest quantum-dot energy shells by resonant inelastic light scattering. These findings open the way to the manipulation of single electrons in these quantum dots without the need of external metallic gates. 
Sokratis Kalliakos, Vittorio Pellegrini, Cesar Pascual Garcia, Aron   Pinczuk, Loren N. Pfeiffer, Ken. W. West