A study of optical reflectance and localization modes of 1-D Fibonacci photonic quasicrystals using different graded dielectric materials

In this paper, we present an analytical study on the reflection properties of light through one-dimensional (1-D) quasi-periodic multilayer structures. The considered structures are as follows: F-7, F-8, F-9, (F-2)(10), (F-3)(10) and some combinations such as: [(F-2)(10)(F-7) (F-2)(10)], [(F2)(10) (F-8)(F-2)(10)], [(F-3)(10)(F-7)(F-3)(10)], [(F-3)(10)(F-8)(F-3)(10)], [(F-2)(10)(F-3)(10)], [(F-2)(10)(F-7) (F-3)(10)] and [(F-2)(10) (F-8)(F-3)(10)], where (F-j)(n) represents n period of the Fibonacci sequence of jth generation. These multilayer structures are considered of two types of layers. One type of layer is considered of graded material like normal, linear or exponential graded material, and the second type of layer is considered of constant refractive index material. Transfer matrix method is utilized to calculate the reflection spectra and localization modes of such structures in the frequency range 150-450 THz. This work would provide the basis of understanding of the effect of graded materials on the reflection and localization modes in Fibonacci photonic quasicrystal structures and obtained spectra can be used in the recognition of grading of materials. The considered heterostructures provide the broad reflection band and some localization modes in the calculated region.