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

摘要

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 linearly polarized reorienting UV light at varying polarization azimuth, φ_p. At non-zero values of the azimuth, φ_p ≠ 0, as opposed to the case where the polarization vector of the light is parallel to the initial easy axis (φ_p = 0), the easy axis reorientation was observed to be most pronounced outside the interelectrode gaps. In the regions between electrodes with non-vanishing electric field, it is found that the dynamics of reorientation slows down with φ_p and the sense of easy axis rotation is independent of the sign of φ_p. A generalized version of the phenomenological model that was previously developed to describe the electrically assisted light-induced gliding is applied to interpret the experimental data.