Effects of polarization azimuth in dynamics of electrically assisted light-induced gliding of nematic liquid-crystal easy axis

TL;DR

This study investigates how the polarization azimuth of UV light influences the reorientation dynamics of nematic liquid crystal easy axes under electric fields, revealing polarization-dependent reorientation behaviors.

Contribution

It provides new experimental insights into the combined effects of electric fields and light polarization azimuth on liquid crystal easy axis reorientation.

Findings

Reorientation occurs outside interelectrode gaps at non-zero polarization azimuths.

Reorientation dynamics slow down as polarization azimuth increases.

Sense of easy axis rotation is independent of the sign of polarization azimuth.

Abstract

We experimentally study the reorientation dynamics of the nematic liquid crystal easy axis at photoaligned azo-dye films under the combined action of in-plane electric field and reorienting UV light linearly polarized at varying polarization azimuth, $\phi_p$. In contrast to the case where the light polarization vector is parallel to the initial easy axis and $\phi_p=0$, at $\phi_p\ne 0$, the pronounced purely photoinduced reorientation is observed outside the interelectrode gaps. In the regions between electrodes with non-zero electric field, it is found that the dynamics of reorientation slows down with $\phi_p$ and the sense of easy axis rotation is independent of the sign of $\phi_p$.