20.500.12556/RUL-144726 Electrically tuneable optical diffraction gratings based on a polymer scaffold filled with a nematic liquid crystal We present an experimental and theoretical investigation of the optical diffractive properties of electrically tuneable optical transmission gratings assembled as stacks of periodic slices from a conventional nematic liquid crystal (E7) and a standard photoresist polymer (SU-8). The external electric field causes a twist-type reorientation of the LC molecules toward a perpendicular direction with respect to initial orientation. The associated field-induced modification of the director field is determined numerically and analytically by minimization of the Landau–de Gennes free energy. The optical diffraction properties of the associated periodically modulated structure are calculated numerically on the basis of rigorous coupled-wave analysis (RCWA). A comparison of experimental and theoretical results suggests that polymer slices provoke planar surface anchoring of the LC molecules with the inhomogeneous surface anchoring energy varying in the range 5–20 µJ/m$^2$. The investigated structures provide a versatile approach to fabricating LC-polymer-based electrically tuneable diffractive optical elements (DOEs). polymers nematic liquid crystals optics diffraction gratings photoresist polymeric materials laser-based micro structuring diffractive optical elements polimeri nematski tekoči kristali lasersko mikrostrukturiranje optika uklonske mrežice true false true Angleški jezik Slovenski jezik Članek v reviji 2023-03-09 14:42:12 2023-03-09 14:42:13 2023-03-22 11:40:45 0000-00-00 00:00:00 2021 0 0 17 str. iss. 14, art. 2292 Vol. 13 Jul. 2021 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 535.421 2073-4360 10.3390/polym13142292 71504131 polymers-13-02292-v2.pdf polymers-13-02292-v2.pdf 1 12A251203302EAA44F4A8CDF63D06D23 518b3a81c2ae3bb067552968c633c56e1c5e001c5a04b6aa286971dd48fcb8a9 4a5586bb-be80-11ed-a314-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=167208 https://www.mdpi.com/2073-4360/13/14/2292 0 3bec6e52-be80-11ed-a314-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=167207 Fakulteta za matematiko in fiziko 0 0 0