METAL-INSULATOR TRANSITIONS AND STRONG ELECTRON CORRELATIONS

Abstract

An overview of lattice models for strongly correlated electrons is given. A detailed study is presented of a model recently introduced by Montorsi and Rasetti. Analytical, exact diagonalization and Quantum Monte Carlo techniques are employed to investigate the static and dynamic properties of this model. The complete ground state phase diagram of the one-, two- and three-dimensional model is given. The Montorsi-Rasetti model is shown to exhibit a metal-insulator transition of the Mott type, independent of the dimensionality of the lattice, and has a ferromagnetic phase. Results for the two-dimensional Montorsi-Rasetti model strongly suggest the occurrence of a phase transition at finite temperatures.