Indications of ${\mathit{d}}_{\mathit{x}}^2$-${\mathit{y}}^2$ superconductivity in the two dimensional t-J model

Supercomputing correlations in the two dimensional t-J model at zero temperature are evaluated using numerical techniques. At the fermionic density 〈n〉∼1/2, strong signals of ${\mathit{d}}_{\mathit{x}}^2$-${\mathit{y}}^2$ superconductivity were observed in the ground state. These conclusions are based on a study of static pairing correlations, the Meissner effect, and flux quantization as indicators of superconductivity. A tentative phase diagram of the two dimensional t-j model is presented.