Superconductivity from correlated hopping

Abstract

We consider a chain described by a next-nearest-neighbor hopping combined with a nearest-neighbor spin flip. In two dimensions this three-body term arises from a mapping of the three-band Hubbard model for CuO$_2$ planes to a generalized $t-J$ model and for large O-O hopping favors resonance-valence-bond superconductivity of predominantly $d$-wave symmetry. Solving the ground state and low-energy excitations by analytical and numerical methods we find that the chain is a Luther-Emery liquid with correlation exponent $K_ρ = (2-n)^2/2$, where $n$ is the particle density.

10 pages, RevTeX 3.0 + 2 PostScript figs. Accepted for publication in Phys.Rev. B