Delocalizing effect of the Hubbard repulsion for electrons on a two-dimensional disordered lattice
Abstract
We study numerically the ground-state properties of the repulsive Hubbard model for spin-1/2 electrons on two-dimensional lattices with disordered on-site energies. The projector quantum Monte Carlo method is used to obtain very accurate values of the ground-state charge density distributions with and particles. The difference in these charge densities allows us to study the localization properties of an added particle. The results obtained at quarter-filling on finite clusters show that the Hubbard repulsion has a strong delocalizing effect on the electrons in disordered 2D lattices. However, numerical restrictions do not allow us to reach a definite conclusion about the existence of a metal-insulator transition in the thermodynamic limit in two-dimensions.
Cite
@article{arxiv.cond-mat/0301623,
title = {Delocalizing effect of the Hubbard repulsion for electrons on a two-dimensional disordered lattice},
author = {Bhargavi Srinivasan and Giuliano Benenti and Dima L. Shepelyansky},
journal= {arXiv preprint arXiv:cond-mat/0301623},
year = {2009}
}
Comments
revtex, 7 pages, 7 figures