Chiral liquid crystal colloids

TL;DR

This paper investigates how the chirality of colloidal particles influences their self-organization within nematic liquid crystals, revealing that chirality can determine the formation of chiral or racemic structures and offering a new tool for controlling liquid crystal colloid arrangements.

Contribution

It demonstrates the role of colloidal particle chirality in directing the mesoscopic order of liquid crystal colloids through experimental and numerical methods.

Findings

Chiral colloids interact with nematic elasticity to form chiral or racemic superstructures.

Chirality influences the global orientational self-organization of liquid crystal colloids.

Numerical modeling confirms experimental observations of chirality effects.

Abstract

Colloidal particles disturb the alignment of rod-like molecules of liquid crystals, giving rise to long-range interactions that minimize the free energy of distorted regions. Particle shape and topology are known to guide this self-assembly process. However, how chirality of colloidal inclusions affects these long-range interactions is unclear. Here we study the effects of distortions caused by chiral springs and helices on the colloidal self-organization in a nematic liquid crystal using laser tweezers, particle tracking and optical imaging. We show that chirality of colloidal particles interacts with the nematic elasticity to predefine chiral or racemic colloidal superstructures in nematic colloids. These findings are consistent with numerical modelling based on the minimization of Landau-de Gennes free energy. Our study uncovers the role of chirality in defining the mesoscopic order of liquid crystal colloids, suggesting that this feature may be a potential tool to modulate the global orientated self-organization of these systems.