D. A. Semerenko | Searcharxiv

arXiv2019

Waveguide propagation of light in polymer porous films filled with nematic liquid crystals

We theoretically analyze the waveguide regime of light propagation in a cylindrical pore of a polymer matrix filled with liquid crystals assuming that the effective radial optical anisotropy is biaxial. From numerical analysis of the dispersion relations, the waveguide modes are found to be sensitive to the field-induced changes of the anisotropy. The electro-optic properties of the polymer porous polyethylene terephthalate (PET) films filled with the nematic liquid crystal 5CB are studied experimentally and the experimental results are compared with the results of the theoretical investigation.

physics.optics↗

arXiv2012

Electrically assisted light-induced gliding of nematic liquid-crystal easy axis at varying polarization azimuth of reorienting light: model and experiment

The phenomenological torque balance model previously introduced to describe the electrically assisted light-induced gliding is generalized to 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, $φ_p$. We systematically examine the general properties of the torque balance model by performing analysis of the bifurcations of equilibria at different values of the polarization azimuth and apply the model to interpret the experimental results. In our experiments, it is found that, in contrast to the case where $φ_p=0$ and the light polarization vector is parallel to the initial easy axis, at $φ_p\ne 0$, the pronounced purely photoinduced reorientation occurs outside the interelectrode gaps. It is also observed that, in the regions between electrodes with non-zero electric field, the dynamics of reorientation slows down with $φ_p$ and the sense of easy axis rotation is independent of the sign of $φ_p$.

cond-mat.soft↗