Light-induced reversible phase transition in a cubic-phase forming system composed of 4'-n-docosaloxy-3'-nitrobiphenyl-4-carboxylic acid (ANBC-22) and azobenzene derivative

Abstract

A thermotropic mesogen 4'-n-alkoxy-3'-nitrobiphenyl-4-carboxylic acid, denoted ANBC-n with n being the number of carbon atoms in the alkoxy tail, forms self-organized bicontinuous cubic mesophase. Azobenzene derivatives are, on the other hand, known to exhibit a UV light-induced trans-cis isomerization. In this work, we prepared cubic binary mixtures containing both cubic-phase forming compound ANBC-22 and an azobenzene derivative having a similar molecular structure. We found that the phase transition of ANBC-22 is induced by the photoisomerization of the azobenzene derivative doped. We investigated the light-driven phase transition behavior of these mixtures by transmitted-light intensity measurements.