Time delay of light propagation through defect modes of one-dimensional photonic band-gap structures

Light propagation through one-dimensional photonic band-gap structures with defect layers embedded at the center was investigated. The localization of the defect mode results in a great delay of propagation time. The average time spent in each layer is given. From the temporal behavior we can deduce the energy distribution in the interior of the photonic band-gap structure and calculate the average velocity of light propagation. The average velocity depends sensitively on the number of layers and the contrast of the refractive indexes.