Universal Scrambling Properties of Spectra and Wave functions in Disordered Interacting Systems

Recent experiments on quantum dots in the Coulomb Blockade regime have shown how adding successive electrons into a dot modifies the energy spectrum and the wave functions of the electrons already present in the dot. Using a microscopic model, we study the importance of electron-electron interaction on these ``scrambling'' effects. We compute the Hartree-Fock single particle properties as function of the number $p$ of added electrons. We define parametric correlation functions that characterize the scrambling properties of the Hartree-Fock wave functions and energy spectra. We find that each of these correlation functions exhibit a universal behavior in terms of the ratio $p/p^{\ast}$ where $p^{\ast}$ is a characteristic number that decreases with increasing either the interaction strength, the disorder strength or the system size