Mott transition in the Hubbard model on the triangular lattice

We investigate a metal-insulator Mott transition in the halffilled Hubbard model on the triangular lattice. In this study, we make use of the path-integral renormalization group method with an iteration and truncation scheme proposed recently, which allows us to access the competing ground states around the transition point. Wefind for a cluster with 36 sites that as the Hubbard interaction U increases, the paramagnetic metallic (PM) state undergoes a metal-insulator phase transition to a nonmagnetic insulating (NMI) state at U_c 7:4t, where t is the transfer integral. A detailed analysis around the transition point shows that the Mott transition is of first order.