Effects of the Next Nearest Neighbor Hopping on Superconductivity and Antiferromagnetism of Gossamer Superconductivity

The two dimensions hole-doped t-t'-J-U model was studied based on the Gutzwiller approach and the renormalized mean-field theory. The phase diagrams of gossamer superconductors and the effects of the next-nearest-neighbor hopping (t') on superconductivity and antiferromagnetism based on the t-t'-J-U model were investigated. The results show that the qualitative feature of the phase diagrams in the t-t'-J-U model is the same as in the case of the t-J-U model. The antiferromagnetic order coexists with the d-wave superconductivity (dSC) in the underdoped region below the doping δ ≈ 0.1 and is enhanced by the t'. The dSC order is slightly suppressed by t' in the underdoped region and greatly enhanced in the overdoped region. The dSC order is pushed to a larger doping region and the coexistence region of the AF and dSC extends to higher doping.