Non-locality and short-range wetting phenomena

TL;DR

This paper introduces a non-local interfacial model for 3D short-range wetting phenomena, explaining the origin of effective potentials and stiffness, and analyzing non-local effects on phase transition order using RG and simulations.

Contribution

It develops a novel non-local model based on the Ornstein-Zernike correlation function, providing insights into wetting behavior and phase transition nature.

Findings

Non-locality significantly influences critical wetting behavior.

The model explains the origin of position-dependent stiffness and binding potential.

Non-perturbative effects of non-locality affect the order of the phase transition.

Abstract

We propose a non-local interfacial model for 3D short-range wetting at planar and non-planar walls. The model is characterized by a binding potential \emph{functional} depending only on the bulk Ornstein-Zernike correlation function, which arises from different classes of tube-like fluctuations that connect the interface and the substrate. The theory provides a physical explanation for the origin of the effective position-dependent stiffness and binding potential in approximate local theories, and also obeys the necessary classical wedge covariance relationship between wetting and wedge filling. Renormalization group and computer simulation studies reveal the strong non-perturbative influence of non-locality at critical wetting, throwing light on long-standing theoretical problems regarding the order of the phase transition.