Fig. 1: Plaquette ground state.
From: Degenerate plaquette physics as key ingredient of high-temperature superconductivity in cuprates
Phase diagram of 2 × 2 plaquette for different particle sectors (N = 2, 3, 4) and zero temperature with the degenerate point marked by star. The circle and and square display the shifted chemical potentials for a test comparison. The region of \({d}_{{x}^{2}-{y}^{2}}\) superconducting phase and normal metal for square lattice are also marked.
