Effect of dominant three-body interaction in two-dimensional square lattice

The effect of dominant three-body interaction to hard-core boson Hubbard model is studied on a two-dimensional square lattice. In terms of quantum Monte Carlo method, it is shown explicitly a ρ = 2/3 solid phase with coexistence of charge-density-wave and bond orders appears due to the presence of the dominant three-body interaction. For strong three-body interaction, the ρ = 2/3 solid phase appears between superfluid phases and shrinks as decreasing the strength of the three-body interaction, forming a lobe structure in the phase diagram. For weak three-body interactions, superfluid phase exists for the whole range of hard-core densities except the full filled case, where the system is a Mott insulator.