# Microsecond electro-optic switching of nematic liquid crystals with giant dielectric anisotropy

## TL;DR

This paper demonstrates a rapid electro-optic switching method in nematic liquid crystals using a material with giant dielectric anisotropy, achieving microsecond response times at lower electric fields than traditional approaches.

## Contribution

It introduces the MEMOP effect, enabling fast birefringence modulation with significantly reduced electric fields in nematic liquid crystals.

## Key findings

- Significant birefringence change (~0.04) with a field of 3×10^7 V/m
- Switching times of approximately 10 microseconds
- Potential applications in fast electro-optic devices

## Abstract

Nematic liquid crystals exhibit a fast optical response when the applied electric field modifies the degree of order but does not change the direction of molecular orientation. The effect requires a relatively high electric field, on the order of 10^8 V/m for a field induced birefringence change of 0.01. To address this detrimental issue, this work explores electrically induced modification of the order parameter in a material with a giant dielectric anisotropy of +200. A relatively weak field 3X10^7 V/m causes a significant change of birefringence, by about 0.04. Both switching on and off times are ~10 microseconds. The effect is called a microsecond electrically modified order parameter (MEMOP) and can be used in electro-optical devices, such as fast electro-optic shutters, phase modulators, and beam-steerers that require microsecond response times.

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Source: https://tomesphere.com/paper/1907.10227