Phase separation of t-J-V model on a triangular lattice: Possible application to heavily doped NaxCoO2

We theoretically investigated the ground state (GS) properties of the single-orbital t-J-V model on a two-dimensional triangular lattice. We found that different interaction parameters are in favor of different charge and spin ordered GS. Moreover, a phase separated GS is stable in the interaction parameter regime of heavily doped NaxCoO2.