Flexoelectricity versus Electrostatics in Polar Nematic Liquid Crystals

TL;DR

This paper develops a theoretical framework to analyze the competition between flexoelectricity and electrostatics in polar nematic liquid crystals, predicting a phase diagram with various phases.

Contribution

It introduces a combined theory of flexoelectricity and electrostatics to understand phase behavior in polar nematic liquid crystals.

Findings

Predicted phase diagram with ferroelectric, antiferroelectric, and nematic phases

Identified the energetic competition between flexoelectricity and electrostatics

Provided insights into phase stability in polar nematic systems

Abstract

Polar nematic liquid crystals have two special features, compared with conventional nematic liquid crystals. First, because of flexoelectricity, the combination of polar order and splay reduces the free energy. Second, because of electrostatics, any splay generates a bound charge density, which increases the free energy. To assess the competition between these two effects, we develop a theory that combines flexoelectricity and electrostatics. The theory predicts a phase diagram that includes ferroelectric, antiferroelectric, and conventional nematic phases.