Exact calculation of the two-electron interaction in the ground state of the Hubbard model
Liang Chen, Changjiang Mei
The single-band Hubbard model has been studied in both the one-dimensional ring and two-dimensional torus. By the exact calculation of the pair correlation function F(i,j), defined as the possibility of finding an electron at site j when there has been an electron at site i, it is shown that for two electrons, the interaction is always repulsive in the ground state for any positive value of the on-site Coulomb interaction U.
Physical review. B, Condensed matter•May 1, 1989•18 citations