Optical intensity-driven reversible photonic bandgaps in self-organized helical superstructures with handedness inversion

An optical intensity-driven self-organized helical superstructure was found to exhibit reversibly dynamic bandgap shifting, a wide bandgap and a hyper-reflection bandgap in one system. According to the UV-intensity dependence of the photo-isomerization ratio of chiral molecular motors, the specialized arrangement of helical pitch with chiral handedness inversion can be directly obtained along the direction of the helical axis upon ultraviolet exposure, which can be evidently observed in liquid-crystalline polymer composites.