Ground state with soliton in one-dimensional t-t'-J-J' model.

Abstract

The one-dimensional t-t'-J-J' model is examined by numerical diagonalization in the case that one hole is doped to the half-filled band. In the presence of t', two types of solitons are found; one is a bound object of the hole and a singlet electron pair in a ferromagnetic background (t'>0, J0), and the other is that of the hole and a triplet electron pair in a singlet background (t'0, J>0). It seems that the solitons remain in the ground state when the system size becomes infinite. The formation of the solitons is ascribed to a kinematic exchange effect due to the t' term.