Electronic structure calculations of quantum dots

Recent experiments revealing the atomic-like spectra in quantum dots call for quantitative theoretical tools. We present a study of the electronic structure of two-dimensional quantum dots up to 58 electrons using Current-Density-Functional Theory (CDFT), which enables us to obtain the ground state energy including the effects of an external magnetic field. We observe a shell structure for the filling of the dot with electrons. Hund's rule determines the spin configuration of the ground state, but only up to 22 electrons. After that, orbital degeneracies are lifted by the non-parabolic effective potential, and high spin states are suppressed. At specific N, a small deformation of the external potential induces a rotational Charge-Density-Wave (CDW) state. In the presence of magnetic fields up to 4.5 T, the dot shows four distinct regimes. We present the magnetic field dependence of the addition spectrum, total angular momentum, and spin configuration.