Band gap characteristics of 1D static and moving photonic crystal

We have studied theoretically the realistic factors for the formation of PBGs in 1D PCs for all incident angles and polarizations, using the transfer matrix method. The results show that these factors significantly influence the behaviour of photonic band characteristics and transmission coefficient, which can be enhanced or suppressed by adjusting the frequency, angle of incidence, optical path length or manipulating the geometry of the 1D PCs. This method can be used conveniently to study the band gap characteristics when the 1D PC moves with uniform velocity. The dielectric constants of the layers are transformed due to motion of the PC. The frequency range of the crystal band gap is shifted towards low frequency with increasing velocity. The moving crystal concept enables novel photonic devices such as optically tunable mirrors, all optical diodes and cavities.