Spinodal Phase Separation in Liquid Films with Quenched Disorder

TL;DR

This study investigates how chemically disordered substrates influence spinodal phase separation in thin liquid films, revealing effects on fluctuation amplification and domain growth stages through simulations.

Contribution

It introduces a detailed simulation analysis of disorder effects on spinodal phase separation, contrasting with traditional phase-separation behavior.

Findings

Disorder affects early fluctuation amplification.

Disorder influences intermediate stages.

Disorder effects vanish in late-stage domain growth.

Abstract

We study spinodal phase separation in unstable thin liquid films on chemically disordered substrates via simulations of the thin-film equation. The disorder is characterized by immobile patches of varying size and Hamaker constant. The effect of disorder is pronounced in the early stages (amplification of fluctuations), remains during the intermediate stages and vanishes in the late stages (domain growth). These findings are in contrast to the well-known effects of quenched disorder in usual phase-separation processes, viz., the early stages remain undisturbed and domain growth is slowed down in the asymptotic regime. We also address the inverse problem of estimating disorder by thin-film experiments.