Slow light offers many opportunities for photonic devices by increasing the effective interaction length of
imposed refractive index changes. The slow wave effect in photonic crystals is based on their unique dispersive
properties and thus entirely dielectric in nature. In this work we demonstrate an interesting opportunity to decrease
drastically the group velocity of light in one-dimensional photonic crystals constructed form materials with large
dielectric constant without dispersion). We use numerical analysis to study the photonic properties of periodic (Bragg
mirror) and quasiperiodic one dimensional photonic crystals realized to engineer slow light effects. Various geometries
of the photonic pattern have been characterized and their photonic band-gap structure analyzed. Indeed, one
dimensional quasi periodic photonic multilayer structure based on Fibonacci, Thue-Morse, and Cantor sequences were
studied. Quasiperiodic structures have a rich and highly fragmented reflectivity spectrum with many sharp resonant
peaks that could be exploited in a microcavity system. A comparison of group velocity through periodic and quasiperiodic
photonic crystals was discussed in the context of slow light propagation. The velocity control of pulses in
materials is one of the promising applications of photonic crystals. The material systems used for the numerical analysis
are TiO2/SiO2 and Te/SiO2 which have a refractive index contrast of approximately 1.59 and 3.17 respectively. The
proposed structures were modelled using the Transfer Matrix Method.
One-dimensional (1D) photonic crystals composed of alternating stacks of layers having a low and a high index of refraction was recently shown to act as omnidirectional reflection band. They reflect light at any polarization, any incidence angle, and over a wide range of wavelengths. In contrast to the three-dimensional case the 1D photonic crystal is attractive since its production is more feasible at any wavelength scale. When a structural defect is introduced in the photonic crystal, photon-localized state can be created in the photonic band gap. In 1D photonic crystal, the defect can be used to open controlled optical windows in the photonic band gap or to obtaining an omnidicrectional photonic band gap. We can find more types of defects that play the role of broking the periodicity of the photonic crystal to produce new physical phenomena or new quasi-periodic systems. A design procedure for omnidirectional high reflectors with wide bandwidths for the optical telecommunication bands is described. From the numerical results performed by the transfer matrix method, it is found that a partially omnidirectional high-reflector covering the optical telecommunication wavelengths 1.3 and 1.55μm is obtained for a quarter-wave stack air/H(LH)12/air by using the tellurium as a materiel of high refractive index (nH=4.6). The study of a deformed stack which be constructed according the quasiperiodic sequences (Fibonacci and Thue-Morse) so that the coordinates y of the deformed object were determined through the coordinates x of the Fibonacci stack in accordance with the following rule y = xk+1 leads to an omnidirectional high reflector band covering the all optical telecommunication wavelengths, here k is the coefficient defining the deformation degree. The reflection properties of one-dimensional generalized Cantor-like multilayer (GCLM) are investigated numerically in the visible range. Strong correlation between the stack geometry and the properties of the optical reflection spectra is found, namely spectral scalability and sequential splitting. The construction of multilayer systems according to the definite Cantor distribution brings improvements to the reflection properties. In particular, the widening of the band gap and the thin peak appearance in the reflection spectra whose number increases with the division number in the (GCLM). Optical properties of (GCLM) inserted between two periodic stacks are numerically investigated. We chose SiO2(L) and TiO2 (H) as two elementary layers. The study configuration is H(LH)j[GCLM]PH(LH)j which forms an effective interferential filter in the visible spectral range. We show that the number of resonator peaks is dependent on the repetition of the number P of the (GCLM). The best performances are obtained in particular for the symmetrical configurations of the (GCLM) and especially for P an odd number.