Hubbard physics in the symmetric half-filled periodic Anderson-Hubbard model
arXiv:1207.0381 · doi:10.3938/jkps.62.1423
Abstract
Two very different methods -- exact diagonalization on finite chains and a variational method -- are used to study the possibility of a metal-insulator transition in the symmetric half-filled periodic Anderson-Hubbard model. With this aim we calculate the density of doubly occupied sites as a function of various parameters. In the absence of on-site Coulomb interaction () between electrons, the two methods yield similar results. The double occupancy of levels remains always finite just as in the one-dimensional Hubbard model. Exact diagonalization on finite chains gives the same result for finite , while the Gutzwiller method leads to a Brinkman-Rice transition at a critical value (), which depends on and .
10 pages, 5 figures