Lattice depth V₀ versus SOC strength γ for different parameters Γ, (a) N_t=10, g=0.6, g₁₂=0.1, and (b) N_t=8, g=0.1, g₁₂=0.6. The parameter plane is divided into different regions by the boundary curves, which are labeled by A, B, C, and D. Hereafter, all the quantities plotted in the figures are dimensionless.