Textures of cholesteric droplets controlled by photo-switching chirality at the molecular level

We demonstrate the ultra-sensitive detection of molecular chirality experimentally, by investigating structural transitions in sessile droplets of cholesteric liquid crystals. By doping the liquid crystal with chiral molecular photo-switches, we demonstrate that both optical and structural transitions can be triggered by light, reversibly. Moreover, we show that depending on the initial confinement state of the cholesteric helix, the expression of chirality can be photo-switched on and off by means of an interplay between microscopic and geometric constraints.