A new dielectric effect in viscous liquids

TL;DR

This study reports a novel dielectric effect in viscous liquids where a long-lasting pipe structure forms after a heavy body passes, revealing complex dynamics and a new microscopic model.

Contribution

The paper introduces the first detailed experimental and theoretical analysis of a new dielectric phenomenon involving persistent pipe structures in viscous liquids.

Findings

Long-lasting pipe structures observed in viscous liquids.

Non-monotonous persistence time with respect to viscosity.

A microscopic thermodynamical model explaining the phenomenon.

Abstract

An accurate experimental and theoretical study has been performed about a phenomenon, not previously reported in the literature, occurring in highly viscous liquids: the formation of a definite pipe structure induced by the passage of a heavy body, this structure lasting for quite a long time. A very rich phenomenology (including mechanical, optical and structural effects) associated with the formation of the pipe has been observed in different liquids. Actually, the peculiar dynamical evolution of that structure does not appear as a trivial manifestation of standard relaxation or spurious effects. In particular we have revealed different time scales during the evolution of the pipe and a non-monotonous decrease of the persistence time with decreasing viscosity (with the appearance of at least two different maxima). We put forward a microscopic model, consistent with the experimental data, where the pipe behaves as a "dielectric shell" whose time evolution is described through a simple thermodynamical approach, predicting several properties effectively observed.