2000/10/20 by M. Mueller, Marcus Müller, Kurt Binder +1 · 1 citation
Materials Science · Mathematics · Physics and Astronomy · #Antisymmetric relation #Block Copolymer Self-Assembly #Condensed matter physics #Critical point (mathematics) #Geometry #Ising model #Material Dynamics and Properties #Materials science #Mathematical physics #Mathematics #Monte Carlo method #Phase (matter) #Phase diagram #Phase transition #Physics #Quantum mechanics #Scaling #Statistical physics #Theoretical and Computational Physics #Tricritical point #cond-mat.soft #cond-mat.stat-mech
paper · pdf · doi:10.1103/physreve.63.021602
Phys.Rev.E
arxiv created 2000/10/20 · openalex publication_date 2001/01/24 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Using extensive Monte Carlo simulations, we study the phase diagram of a symmetric binary (AB) polymer blend confined into a thin film as a function of the film thickness D. The monomer-wall interactions are short ranged and antisymmetric, i.e., the left wall attracts the A component of the mixture with the same strength as the right wall does the B component, and this gives rise to a first order wetting transition in a semi-infinite geometry. The phase diagram and the crossover between different critical behaviors is explored. For large film thicknesses we find a first order interface localization-delocalization transition, and the phase diagram comprises two critical points, which are the finite film width analogies of the prewetting critical point. Using finite-size scaling techniques we locate these critical points, and present evidence of a two-dimensional Ising critical behavior. When we reduce the film width the two critical points approach the symmetry axis straight phi=1/2 of the phase diagram, and for D approximately 2R(g) we encounter a tricritical point. For an even smaller film thickness the interface localization-delocalization transition is second order, and we find a single critical point at straight phi=1/2. Measuring the probability distribution of the interface position, we determine the effective interaction between the wall and the interface. This effective interface potential depends on the lateral system size even away from the critical points. Its system size dependence stems from the large but finite correlation length of capillary waves. This finding gives direct evidence of a renormalization of the interface potential by capillary waves in the framework of a microscopic model.