Role of Thermal Fluctuations in Nonlinear Thin Film Dewetting

TL;DR

This paper investigates how thermal fluctuations influence the nonlinear stages of thin film dewetting, revealing that noise accelerates droplet formation, alters droplet count and distribution, and impacts long-term coarsening.

Contribution

It introduces a stochastic lubrication model to analyze the role of thermal noise in thin film dewetting, highlighting its effects on droplet dynamics and pattern formation.

Findings

Thermal fluctuations speed up droplet formation.

Stochastic systems have fewer, more variable droplets.

Thermal noise affects long-term droplet coarsening.

Abstract

The spontaneous formation of droplets via dewetting of a thin fluid film from a solid substrate allows for materials nanostructuring, under appropriate experimental control. While thermal fluctuations are expected to play a role in this process, their relevance has remained poorly understood, particularly during the nonlinear stages of evolution. Within a stochastic lubrication framework, we show that thermal noise speeds up and substantially influences the formation and evolution of the droplet arrangement. As compared with their deterministic counterparts, for a fixed spatial domain, stochastic systems feature a smaller number of droplets, with a larger variability in sizes and space distribution. Finally, we discuss the influence of stochasticity on droplet coarsening for very long times.