Laser induced rotation of trapped chiral and achiral nematic droplets

TL;DR

This paper investigates how optically trapped nematic liquid crystal droplets, both achiral and chiral, respond to polarized light, revealing different rotation behaviors and dissipation mechanisms.

Contribution

It demonstrates that chiralized nematic droplets can rotate under linearly polarized light and provides a new scaling law for their rotational frequency.

Findings

Achiral droplets exhibit internal dissipation during rotation.

Chiralized droplets rotate under linearly polarized light.

Rotational frequency scales approximately as 1/R^2 for chiralized droplets.

Abstract

We study the response of optically trapped achiral and chiralised nematic liquid crystal droplets to linear as well as circular polarised light. We find that there is internal dissipation in rotating achiral nematic droplets trapped in glycerine. We also demonstrate that some chiralised droplets rotate under linearly polarised light. The best fit to our data on chiralised droplets indicates that rotational frequency of these droplets with radius R is approximately proportional to1/R^2, rather than to 1/R^3.