Slowing down the light in the photonic crystals

Slow light has been an intense research area for more than two decades. Researchers has sought for efficient ways of slowing down the light because slow light pave the way to optical devices such as optical buffers, delay lines, and nonlinear elements that can be used to convert the wavelength of the light. The attempts for slowing down the light are carried out in two different categories. The first category utilizes extraordinary material properties such as atomic resonances and solid state structures. The second category employs structural dispersion of linear materials, such as photonic crystals. Photonic crystals are distinctive elements of photonic devices that show photonic band gap property. By imposing defects into photonic crystals, devices can be achieved that confine the light in these defects, such as waveguides and cavities. By special designs of these types of photonic structures, slow light waveguides and high quality factor cavities can be attained. The first aim of the thesis is slowing down the light speed in photonic crystal waveguides with structural modifications. The second aim of the thesis is to obtain slow light with a large bandwidth. The last concern of the thesis is to solve the transition problem of fast light to slow light and back from slow light to fast light. By novel designs of photonic crystal structures that provide slow light propagation, the efficiency of information processing systems can be increased by avoiding the electro-optic conversions.