JournalsjemsVol. 18, No. 5pp. 931–995

Scaling limit and cube-root fluctuations in SOS surfaces above a wall

  • Pietro Caputo

    Università degli studi Roma Tre, Italy
  • Eyal Lubetzky

    New York University, USA
  • Fabio Martinelli

    Università degli Studi Roma Tre, Italy
  • Allan Sly

    University of California at Berkeley, USA
  • Fabio L. Toninelli

    École Normale Supérieure de Lyon, France
Scaling limit and cube-root fluctuations in SOS surfaces above a wall cover
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Consider the classical (2+1)(2+1)-dimensional Solid-On-Solid model above a hard wall on an L×LL \times L box of Z2\mathbb Z^2. The model describes a crystal surface by assigning a non-negative integer height ηx\eta_x to each site xx in the box and 0 heights to its boundary. The probability of a surface configuration η\eta is proportional to exp(βH(η))\mathrm {exp}(-\beta \mathcal{H}(\eta)), where β\beta is the inverse-temperature and H(η)\mathcal{H}(\eta) sums the absolute values of height differences between neighboring sites.

We give a full description of the shape of the SOS surface for low enough temperatures. First we show that with high probability (w.h.p.) the height of almost all sites is concentrated on two levels, H(L)=(1/4β)logLH(L) = \lfloor (1/4\beta)\mathrm {log} L \rfloor and H(L)1H(L)-1. Moreover, for most values of LL the height is concentrated on the single value H(L)H(L). Next, we study the ensemble of level lines corresponding to the heights (H(L),H(L)1,)(H(L),H(L)-1,\ldots). We prove that w.h.p.\ there is a unique macroscopic level line for each height. Furthermore, when taking a diverging sequence of system sizes LkL_k, the rescaled macroscopic level line at height H(Lk)nH(L_k)-n has a limiting shape if the fractional parts of (1/4β)logLk(1/4\beta)\mathrm {log} L_k converge to a noncritical value. The scaling limit is an explicit convex subset of the unit square QQ and its boundary has a flat component on the boundary of QQ. Finally, the highest macroscopic level line has Lk1/3+o(1)L_k^{1/3+o(1)} fluctuations along the flat part of the boundary of its limiting shape.

Cite this article

Pietro Caputo, Eyal Lubetzky, Fabio Martinelli, Allan Sly, Fabio L. Toninelli, Scaling limit and cube-root fluctuations in SOS surfaces above a wall. J. Eur. Math. Soc. 18 (2016), no. 5, pp. 931–995

DOI 10.4171/JEMS/606