Superfast Thinning of a Nanoscale Thin Liquid Film

TL;DR

This study demonstrates how thermal convection induced by localized cooling accelerates the thinning process of a nanoscale aqueous film from linear to exponential rates, revealing complex fluctuation-driven dynamics.

Contribution

It introduces a novel experimental setup showing superfast thinning of nanoscale films driven by thermal convection, advancing understanding of interfacial fluid dynamics.

Findings

Thermal convection causes exponential thinning of the film.

Localized cooling induces two convection rolls at high Rayleigh number.

Fluctuations significantly alter the film's thinning behavior.

Abstract

This fluid dynamics video demonstrates an experiment on superfast thinning of a freestanding thin aqueous film. The production of such films is of fundamental interest for interfacial sciences and the applications in nanoscience. The stable phase of the film is of the order $5-50\,nm$; nevertheless thermal convection can be established which changes qualitatively the thinning behavior from linear to exponentially fast. The film is thermally driven on one spot by a very cold needle, establishing two convection rolls at a Rayleigh number of $10^7$. This in turn enforces thermal and mechanical fluctuations which change the thinning behavior in a peculiar way, as shown in the video.