Effective interface Hamiltonians for short-range critical wetting

Abstract

The derivation of effective interface Hamiltonians on the basis of an underlying noncritical bulk order-parameter theory is critically examined for use in studying critical wetting transitions in (d=3)-dimensional systems with short-range forces. A crossing constraint on the interfacial profile is used to define the fluctuating interface location l(y) and exact general expressions are obtained for the effective wall-interface potential W[l(y)] and for the wall-modified interfacial stiffness Σ[l(y)] in terms of a constrained planar order-parameter profile. Previous discussions in the literature are shown to be inadequate