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.Comment: revised extended version, to appear in Philos. Mag.B82 (M. Pollak Festschrift

Statistics of resonances in one-dimensional disordered systems

The paper is devoted to the problem of resonances in one-dimensional disordered systems. Some of the previous results are reviewed and a number of new ones is presented. These results pertain to different models (continuous as well as lattice) and various regimes of disorder and coupling strength. In particular, a close connection between resonances and the Wigner delay time is pointed out and used to obtain information on the resonance statistics.Comment: Submitted to the special issue, in memory of Y. Levinson, of the Lithuanian Journal of Physic