Structural heterogeneity: a topological characteristic to track the time evolution of soft matter systems

TL;DR

This paper introduces structural heterogeneity, a novel topological measure for semi-ordered soft matter systems, enabling detailed tracking of their structural evolution and phase transitions at the mesoscopic scale.

Contribution

It presents a new quantitative method to characterize the structural dynamics of complex soft matter systems, capturing order-disorder transitions with high sensitivity.

Findings

Successfully tracked phase transitions in liquid crystal nanocomposites

Revealed effects of confined geometry on phase behavior

Uncovered physical differences between nematic and isotropic transitions

Abstract

We introduce structural heterogeneity, a new topological characteristic for semi-ordered materials that captures their degree of organisation at a mesoscopic level and tracks their time-evolution, ultimately detecting the order-disorder transition at the microscopic scale. Such quantitative characterisation of a complex, soft matter system has not yet been achieved with any other method. We show that structural heterogeneity can track structural changes in a liquid crystal nanocomposite, reveal the effect of confined geometry on the nematic-isotropic and isotropic-nematic phase transitions, and uncover physical differences between these two processes. The system used in this work is representative of a class of composite nanomaterials, partially ordered and with complex structural and physical behaviour, where their precise characterisation poses significant challenges. Our newly developed analytic framework can provide both a qualitative and a quantitative characterisations of the dynamical behaviour of a wide range of semi-ordered soft matter systems.