Interactions in chaotic nanoparticles: Fluctuations in Coulomb blockade peak spacings

Journal Article

We use random matrix models and a Fermi-liquid approach to investigate the ground state energy of electrons confined to a nanoparticle. Our expression for the energy includes the charging effect, the single-particle energies, and the residual screened interactions treated in Hartree-Fock. This model is applicable to chaotic quantum dots or nanoparticles - in these systems the single-particle statistics follows random matrix theory at energy scales less than the Thouless energy. We find the distribution of Coulomb blockade peak spacings first for a large dot in which the residual interactions can be taken constant: the spacing fluctuations are of order the mean level separation Δ. Corrections to this limit are studied using the small parameter 1/kFL: both the residual interactions and the effect of the changing confinement on the single-particle levels produce fluctuations of order Δ/√kFL. The distributions we find are qualitatively similar to the experimental results. Thus, models beyond Fermi-liquid theory are not needed to describe this quantity.

Duke Authors

Cited Authors

  • Ullmo, D; Baranger, HU

Published Date

  • 2001

Published In

Volume / Issue

  • 64 / 24

Start / End Page

  • 2453241 - 24532413

International Standard Serial Number (ISSN)

  • 0163-1829