Orientational Coupling Amplification in Ferroelectric Nematic Colloids

TL;DR

This paper explores how ferroelectric particles in nematic colloids significantly amplify orientational coupling, leading to increased order and higher clearing temperatures, supported by experimental and theoretical analysis.

Contribution

It introduces a theoretical model explaining the amplification of nematic orientational coupling due to ferroelectric particles in colloids.

Findings

Nematic coupling increases by 10% at 0.2% particle concentration.

Clearing temperature rises up to 40°C in colloids compared to pure liquid crystals.

Theoretical model links local dipoles to enhanced orientational order.

Abstract

We investigated the physical properties of low concentration ferroelectric nematic colloids, using calorimetry, optical methods, infra-red spectroscopy and capacitance studies. The resulting colloids normally remain homogeneous, but the nematic orientational coupling is significantly amplified. In particular cases, the nematic orientation coupling increases by 10% for particle concentrations of 0.2%. A manifestation of the increased orientational order is that the clearing temperature of a nematic colloid increases up to 40 Celsius degrees compared to the pure LC host. A theoretical model is proposed in which the ferroelectric particles induce local dipoles whose effective interaction is proportional to the square of the orientational order parameter.