THE NAGAOKA STATE IN THE ONE-BAND HUBBARD-MODEL WITH 2 AND MORE HOLES

The infinite-U Hubbard model with two holes on a two-dimensional square lattice is explicitly studied. We show that the energy of the Nagaoka state and the exact ground state become degenerate in the thermodynamic limit, i.e. there exists no energy gap between the ground state and the first excited state. Finally, we discuss briefly how to generalize this result to cases in which there is a finite number of holes and the structure of the lattice is more complicated.Physics, MultidisciplinaryPhysics, MathematicalSCI(E)7ARTICLE2513-5212