Ferroelectric nematic -- isotropic critical end point

TL;DR

This paper reports the discovery of a critical end point in ferroelectric nematic liquid crystals, where an isotropic phase transitions into a polar nematic phase under an electric field, enabling broad birefringence control.

Contribution

It identifies and characterizes a critical end point in ferroelectric nematic materials, highlighting its potential for optical applications.

Findings

Critical end point is about 30 K above zero-field transition temperature.

Transition occurs at an electric field of approximately 10 V/micron.

Strong birefringence can be induced over a broad temperature range.

Abstract

A critical end point above which an isotropic phase continuously evolves into a polar (ferroelectric) nematic phase with an increasing electric field is found in a ferroelectric nematic liquid crystalline material. The critical end point is approximately 30 K above the zero-field transition temperature from the isotropic to nematic phase and at an electric field of the order of 10 V/micron. Such systems are interesting from the application point of view because a strong birefringence can be induced in a broad temperature range in an optically isotropic phase.