Superconductivity of Carriers Doped into the Static Charge Density Wave State in 2-Dimensional Square Lattice

On the purpose of studying the effect of long-range Coulomb-interaction in strongly correlated electronic systems we bring in as its representative the nearest-neighbor repulsion (v) in addition to the on-site repulsion (u) and shall investigate the possibility of the superconducting transition of carriers doped into the charge-density wave (CDW) state expected for v > u/4 in 2-dimensional square lattice. We shall see that strongly correlated hopping processes of doped carriers make the systems superconducting. The favored superconducting phase is of extended s-wave symmetry, and T_c ~ 100 K is shown to easily be attained near the half-filling.