抄録
Recently, photonic band gap (PBG) crystals with lattice parameters comparable to the wavelength of light have attracted much attention because of their unique optical properties. For many potential applications, it is important to have the capability of tuning the photonic band structures. We report new type of switchable PBG crystals by taking advantage of photo-induced phase transition of liquid crystals. The mixture of nematic liquid crystals and azo dyes was infiltrated into inverse opal films. A dynamic change in the optical stop band could be observed by light irradiation. Such photo-switchable PBG crystals provide a method by which light can be routed using light.