Effect of the three-center terms on the chiral superconducting d-wave pairing of the Hubbard fermions on the triangular lattice

Using the diagram technique for the Hubbard operators an integral equation that determines the order parameter of the superconducting phase was obtained in the framework of t–J–V and t–J*–V models on triangular lattice. It is shown that there are two scenarios of formation of superconducting phase with gapless spectrum at the critical concentration of carriers x_c. The effect of three-center terms on implementation of this phase was also considered.