Reversible Alignment Change of Liquid Crystals Induced by Photochromic Molecular Films

Abstract

The alignment relaxation of nematic liquid crystals regulated by the photochromic reaction of azobenzene (Az) monolayer on substrates was measured upon excitation with an excimer laser. The time of the relaxation between the homeotropic and the parallel alignments resided in the range of 50 and 300 ms, depending on the cell conditions, which values were identical with the electro-optical decay time reported.