Ferroelectricity in the nematic liquid crystal under the direct current electric field

TL;DR

This study explores how direct current electric fields induce ferroelectricity in nematic liquid crystals, revealing new ferroelectric modes, polarization behaviors, and a model considering domain structures.

Contribution

It demonstrates the creation of ferroelectric order in nematic phases under DC fields and introduces a new model for collective and molecular relaxations.

Findings

DC field induces ferroelectric order in nematic phase

Spontaneous polarization exhibits a maximum at fixed temperature

Ferroelectric mode and dielectric properties depend on temperature and field

Abstract

We investigated the electrical properties of the liquid crystal compound, known as an RM734, exhibiting a ferroelectric nematic phase. The influence of alternating (AC) and direct (DC) current electric fields on the switching process of the polarization vector and dielectric constant of planarly aligned ferronematic and nematic phases were examined. The decrease of the real part of electric permittivity in the ferronematic phase and the creation of ferroelectric order in the nematic phase under the DC field were demonstrated. The analysis of the results reveals the latching of the ferroelectric state. The applied DC field created a ferroelectric mode in the nematic phase. A new model of collective and molecular relaxations considering the domain structure of the ferronematic phase was proposed. The temperature and DC field dependence of dielectric properties were shown. The spontaneous polarization was measured using the field reversal technique. The spontaneous polarization value exhibits a maximum at the fixed temperature.