New Communication in Adv. Mater.

Dynamic modulation of photonic bandgaps in crystalline colloidal arrays is achieved by application of electric field. Highly charged polystyrene particles spontaneously create the crystal lattice, which is compressed or relaxed under external electric field by electrokinetic force. As a result, structural color of colloidal crystals as a photonic bandgap can be tuned or fixed with unprecedentedly fast and precise manner.