Fluctuation of the phase boundary in the six-vertex model with domain wall boundary conditions: a Monte Carlo study

We consider the six-vertex model with domain wall boundary conditions in a square lattice of dimension N × N. Our main interest is the study of the fluctuations of the extremal lattice path about the arctic curves. We address the problem through Monte Carlo simulations. At Δ = 0 , the fluctuations of the extremal path along any line parallel to the square diagonal were rigorously proven to follow the Tracy-Widom distribution. We provide strong numerical evidence that this is true also for other values of the anisotropy parameter Δ ( 0 ⩽ Δ < 1 ). We argue that the typical width of the fluctuations of the extremal path about the arctic curves scales as N 1 / 3 and provide a numerical estimate for the parameters of the scaling random variable.