We report the application of the density-matrix renormalization-group method to a spatially anisotropic two-dimensional Hubbard model at half filling. We find a deconfinement transition induced by the transverse hopping parameter $t_y$ from an insulator to a metal. Therefore, if $t_y$ is fixed in the metallic phase, increasing the interaction $U$ leads to a metal-to-insulator transition at a finite critical $U$. This is in contrast to the weak-coupling Hartree-Fock theory which predicts a nesting-induced antiferromagnetic insulator for any $U>0$.

• Received 24 July 2011

DOI:https://doi.org/10.1103/PhysRevB.84.193103