Axial and polar orientational changes by rubbing/photoalignment processes in a liquid crystal alignment layer studied by optical second-harmonic generation
Title
Axial and polar orientational changes by rubbing/photoalignment processes in a liquid crystal alignment layer studied by optical second-harmonic generation
Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers vol. 40, no. 4 A, pp. 2387 - 2390
Indexed
SCIE; SCOPUS
Document Type
Article
Abstract
Molecular reorientation by rubbing and photoalignment processes in polymer alignment layer for liquid crystals has been studied by linear optical absorption and surface optical second-harmonic generation. It was found that rubbing produces polar and axial orders in the photoisomerizable polyamic acid (PAA) containing azobenzene groups in the main chain, while photoalignment after rubbing destroys the polar order but is capable of reorienting the PAA main chain without creating further polar order.