Resolution improvement of order parameter modulation in terms of lifetime of trans-cis isomerization

Abstract

Molecular manipulator is a method of controlling the concentration distribution of guest molecules in a nematic liquid crystal host with azobenzene additive. Localized irradiation with excitation light induces trans to cis photoisomerization of the azo molecules [1], causing migration of guest molecules in response to spatial modulation of the order parameter. However, cis azobenzene molecules are able to diffuse away from the edge of the irradiated region, blurring the boundary and limiting its applications as a local manipulator. Here, we overcome this issue by using a “push-pull” azobenzene which has significantly shorter cis lifetime, realizing a patterning resolution approximately 10 times that of previous work [2].