title: Apparent First-Order Wetting and Anomalous Scaling in the Two-Dimensional Ising Model.
abstract: The global phase diagram of wetting in the two-dimensional Ising model is obtained through the exact calculation of the surface excess free energy. In addition to a surface field for inducing wetting, a surface-coupling enhancement is also included. The wetting transition (of second order) is critical for any finite ratio of surface coupling J_{s} to bulk coupling J, and becomes of first order in the limit J_{s}/J→∞. However, for J_{s}/J≫1, the critical region is exponentially small and is practically invisible to numerical studies. A distinct preasymptotic regime exists in which the transition displays first-order character. In this regime, surprisingly, the surface susceptibility and surface specific heat develop a divergence and show anomalous scaling with an exponent equal to 3/2.
authors.affiliation: Department of Physics, Beijing Normal University, Beijing 100875, China.|Institute for Theoretical Physics, KU Leuven, BE-3001 Leuven, Belgium.
authors.forename: X-T
authors.initials: XT
authors.lastname: Wu
authors.affiliation: NYUSH-ECNU Institute of Mathematical Sciences, 3663 Zhongshan Road North, Shanghai 200062, China.
authors.forename: D B
authors.initials: DB
authors.lastname: Abraham
authors.affiliation: Institute for Theoretical Physics, KU Leuven, BE-3001 Leuven, Belgium.
authors.forename: J O
authors.initials: JO
authors.lastname: Indekeu