EXCITATION-SPECTRA OF CIRCULAR, FEW-ELECTRON QUANTUM DOTS

Studies of the ground and excited states in semiconductor quantum dots containing 1 to 12 electrons showed that the quantum numbers of the s tates in the excitation spectra can be identified and compared with ex act calculations. A magnetic field induces transitions between the gro und and excited states. These transitions were analyzed in terms of cr ossings between single-particle states, singlet-triplet transitions, s pin polarization, and Hund's rule. These impurity-free quantum dots al low ''atomic physics'' experiments to be performed in magnetic field r egimes not accessible for atoms.