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

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, phi(p). At non-zero values of the azimuth, phi(p) not equal 6 0, as opposed to the case where the polarization vector of the light is parallel to the initial easy axis (phi(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 phi(p) and the sense of easy axis rotation is independent of the sign of phi(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. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3701781]