| Abstract: | An exact diagonalization calculation of the t-J model on 2D square cluster has been studied for the ground state properties
of HTSC. Effect of next-nearest-neighbour hopping and magnetic (both antiferromagnetic and ferromagnetic) interaction on d
x
2−y
2-wave pairing has been shown. Relative strength of the next-nearest-neighbour interaction with respect to that of near-neighbour
interaction for the strongest d
x
2−y
2-wave pairing has been estimated. A schematic phase diagram is shown. It is shown that a two-sublattice model with antiferromagnetic
interaction between them and a small intra-ferromagnetictype interaction in one sublattice favours d
x
2−y
2-wave superconductivity and moderate negative type NNN hopping adds flavours to this phase. |
