Progress of electrically responsive photonic crystals

In nature, many species can protect themselves and communicate with peers by changing their body color, which innovates the significant applications of the color variation in security, communication as well as other visual areas. Electrically responsive photonic crystals (PCs) are the most promising tunable photonic systems to imitate the nature and to apply in real technological applications. Recently many electrically responsive PCs have been demonstrated and show great advantages for versatile optical devices. According to the design strategies of the electrically responsive PCs, they are classified into four categories: (1) electrophoretic organization of recyclable colloidal systems, (2) electroactive materials induced colloidal crystal lattice constant variation, (3) inverse opals made from electrically responsive materials and (4) electrically recyclable infiltration in porous photonic structures. In this Review, the design and fabrication of the electrically responsive PCs for functional optical devices are covered and the next steps for this important field are described.