Few correlated particles in the Hubbard model

The ground state binding energy of few particles in an infinite one-dimensi onal periodic and quasiperiodic lattice is investigated rigorously in a Hub bard-Iike model, using a real-space method. We studied the three-body probl em in the periodic lattice with correlated hoppings, for the case of non-pa rallel spin in an infinite linear chain, applying the generalized Hubbard H amiltonian. The correlation is studied for different values of the hopping parameters as well as the on-site and the inter-site interactions. The resu lts show an effect of the frustration of antibonding states on the pairing behavior. In the case of one-dimensional quasiperiodic lattice we give some preliminary results for two electrons with non-parallel spin. (C) 1999 Els evier Science B.V. All rights reserved.