Large Supramolecular Patterns in Photoactive Chiral Liquid Crystals for Light‐Controllable Soft Micromechanical Systems

This study advances fundamental knowledge about the regular dynamic behavior of supramolecular self‐assembled structures formed and remotely controlled by light in chiral nematic liquid crystals. The main focus of this study is on revolving chiral patterns induced by ultraviolet light in frustrated films of photoactive chiral nematics. While the size of the localized pattern and its rotation frequency are determined by the power of the recording light beam, the uniformity and regularity of the rotation depend on the ratio of the localized pattern size to the light spot diameter. When this ratio reaches about eight, the rotation of the supramolecular pattern becomes nonuniform or even interrupted. This is explained by light‐induced processes at both the molecular and supramolecular levels, causing the director field distortions of the revolving structure. Adjusting the diameter of the light spot efficiently restores the regular revolving behavior. Understanding the relationship between the light beam parameters, the characteristics of a supramolecular chiral pattern, and its behavioral features opens up prospects for the use of localized liquid crystal structures as dynamic elastic transporters of micro‐ and nanoscale objects for light‐controllable soft micromechanical systems.