Variational Monte Carlo study of Hubbard model with harmonic confinement

We study the ground-state properties of the fermionic Hubbard model with harmonic confinement, by combining the variational Monte Carlo simulations with the new stochastic method proposed by Sorella. By taking the effect of the confining potential into account, we demonstrate that the metallic regions coexist with the Mott insulating regions in the system, which is consistent with other numerical results. The role of the intersite doublon-holon correlations in the confined system is also addressed