Light-Induced Director Reorientation in Nematic Liquid Crystals Doped with Azobenzene-Containing Macromolecules of Different Architecture

Phase Structure Recording in a Nematic Side-Chain Liquid-Crystalline Polymer

“…At normal light incidence (α = 0 • , threshold geometry), the required exposure time was hours, while at an oblique incidence (non-threshold geometry, α = 35 • ) it was tens of minutes. The light-induced director deformation results in a formation of the aberrational ring pattern in the far field (effect of aberrational light self-action) [10]. We used this pattern to control the recording process.…”

“…As an experimental material we used the side-chain polymer, containing polyacrylate backbone, spacer having five methylene groups, and phenyl benzoate mesogenic fragment (PAA). Its structural formula is Polymers 2020, 12, x FOR PEER REVIEW 2 of 16 [10], formation of light waveguides [11,12], light induced gratings [13], and pattern formation [14]. All these phenomena are related to various structures of deformed director field.…”

“…The nonlinearity of optically transparent NLCs is nine orders of magnitude higher than the Kerr nonlinearity of CS 2 [7]; it can be increased by two orders of magnitude by dye doping [4]. Among the wide variety of nonlinear optical phenomena in NLCs, there are aberrational self-focusing [8,9] and self-defocusing [10], formation of light waveguides [11,12], light induced gratings [13], and pattern formation [14]. All these phenomena are related to various structures of deformed director field.…”