Polarization gratings spontaneously formed by the helical Twist-Bend Nematic phase

TL;DR

This paper reports the spontaneous formation of polarization gratings in twist-bend nematic liquid crystals, which can be used for low-cost optical modulators and beam steering, with properties tunable by temperature.

Contribution

It demonstrates spontaneous polarization grating formation in the NTB phase without surface patterning, highlighting potential applications in tunable optical devices.

Findings

Polarization gratings form spontaneously in the NTB phase.

The gratings enable low-cost, tunable optical modulation.

Diffracted light analysis reveals 3D optic axis variation.

Abstract

Spontaneous formation of polarization gratings by liquid crystals made of bent dimeric molecules is reported. The grating is formed within the temperature range of the twist bend modulated nematic phase, NTB, without the necessity to pattern the cell surfaces, therefore the modulated nematic phase is a promising candidate for low-cost modulators and beam steering devices, the polarization properties of which can be tuned by temperature. In addition, the study of the diffracted light properties turns out to be a sensitive measuring technique for determination of the 3D spatial variation of the optic axis in the cell.