A Model for Addition Spectra in Quantum Dots

A simple model for addition spectra in quantum dots is proposed and studied. It is an extension of the standard charging model which assumes that the charge spreads uniformely over the entire dot. The proposed model attempts to account for a nonuniform distribution of the charge, by introducing an extra parameter U. When U increases, the distribution of the conductance peak spacings changes from the Wigner-Dyson shape towards a broader, more symmetric distribution.