STATISTICS OF THE CHARGING SPECTRUM OF A 2-DIMENSIONAL COULOMB-GLASS ISLAND

The fluctuations of capacitance of a two-dimensional island are studie d in the regime of low electron concentration and strong disorder, whe n electrons can be considered classical particles. The universal capac itance distribution is found, with the dispersion being of the order o f the average. This distribution is shown to be closely related to the shape of the Coulomb gap in the one-electron density of states of the island. Behavior of the capacitance fluctuations near the metal-insul ator transition is discussed.