Coexistence of antiferromagnetism and d-wave superconductivity in extended t-J model

We study the extended t-J model on a square lattice, which has the second and third-neighbor hopping terms (t' and t'', respectively) as well as the nearest-neighbor one using the slave-boson mean-field approximation. It is found that the phase diagram consistent with the experiments for multilayer high-Tc cuprates is obtained for a suitable choice of t' and t''. Temperature dependence of the uniform spin susceptibility is also calculated in the coexistence of antiferromagnetism and d-wave superconductivity.