Fig. 3: Spin structure factor.
From: A resonant valence bond spin liquid in the dilute limit of doped frustrated Mott insulators

Dependence of the ground-state spin structure factor S(Q) (for all individual reciprocal lattice points Q) on J/t (t > 0) for a 16-site system. Left, the system is doped with one hole. The region where the correlations are antiferromagnetic, despite the ferromagnetic J, is shaded. Right, the system is doped with one electron, for comparison.