Optics and Photonics Society of Iran

The ability to extreme slow down the electromagnetic group velocity using photonic crystals is an active research area. Hitherto, different photonic structures have been proposed and investigated both theoretically and experimentally. One of the important limit in slowing light down to zero is the delay-bandwidth product in optical systems. However, there is one proposed method in the literature in order to go beyond this limit so-called dynamic tuning for stopping light. According to this method, at least two cavity in a unit cell are needed to couple to photonic crystal waveguide coherently in order to form cavity-like modes in the structure. In this article, the possibility of eliminating the cavities and considering them as a geometrical defect in photonic crystal structure to introduce a line defect as a waveguide is investigated numerically for stopping light through finite-difference time-domain method. The proposed method is based on making use of both spectral dispersion and the geometrical defect which is introduced to the photonic crystal structure leading to cavity-like modes excitation in whole range of the wavevector component.