Photonic band gap effect and localization in two-dimensional Penrose lattice

Summary form only given. Photonic crystals are artificial periodic structures in which the refractive index modulation gives rise to stop bands for electromagnetic waves (EM) within a certain frequency range in all directions. Recently it was recognized that the photonic gaps can exist in two-dimensional (2D) octagonal quasicrystals. A quasiperiodic system is characterized by a lack of long range periodic translational order. But the quasiperiodic system has long-range band orientational order, so that it can be considered as an intermediate between periodic and random systems. In this work, we report on observation of the photonic band gap effect in a 2D Penrose quasicrystal consisting of dielectric rods. Defect characteristics of various inequivalent sites of the crystal were investigated. The Penrose tiles are composed of fat and skinny rhombic unit cells and fill the 2D plane nonperiodically.