On the Momentum of Doped Carriers in Strongly Correlated Electron Systems

Abstract

In strongly correlated systems the propagation of doped carriers always accompanies rearrangements of other particles so that it is inevitably an involved many-body problem. In this paper the momentum of the lowest-energy doped carriers is studied by determining exactly the ground state of small clusters. A comparative investigation is made on one-band and two-band systems: one-band Hubbard model in one and two dimensions and two-dimensional CuO₂ model. Implications of the results are discussed in connection with high-T_c cuprates.