Asymptotic Behavior of Inflated Lattice Polygons

We study the inflated phase of two dimensional lattice polygons with fixed perimeter N and variable area, associating a weight exp[pA− Jb] to a polygon with area A and b bends. For convex and column-convex polygons, we show that 〈A〉/Amax = 1−K(J)/p̃ 2 + O(ρ), where p̃ = pN ≫ 1, and ρ < 1. The constant K(J) is found to be the same for both types of polygons. We argue that self-avoiding polygons should exhibit the same asymptotic behavior. For self-avoiding polygons, our predictions are in good agreement with exact enumeration data for J = 0 and Monte Carlo simulations for J 6= 0. We also study polygons where self-intersections are allowed, verifying numerically that the asymptotic behavior described above continues to hold.