Abstract
In this paper, we have studied the focusing behavior of two-dimensional Graded Index (GRIN) Photonic Crystal (PC). Two different structures have been considered which were labeled as the structure type Ι and the structure type ΙΙ. To create an index gradient, the rods (holes) radii have been varied along the direction transverse to the propagation. Several optical phenomena such as focusing, de-focusing, and collimation have been investigated regarding structure type I. Also, the focusing effect has been analyzed for the GRIN PC structure type I and type II. In addition, detailed investigations were carried out by comparing the focusing characteristics of two structures. The obtained results have illustrated that the GRIN PC type II represents stronger focusing characteristics in comparison to the GRIN PC type I. Furthermore, by increasing the structural length of both GRIN PCs while the normalized frequency of incoming wave is constant, the focal length decreases although the concentration intensity rises..
Keywords
Photonic crystal, Graded index photonic crystal, Effective refractive index, Focusing effect.
Citation
A. GHARAATI, N. MIRI, On focusing properties of graded index photonic crystals, Optoelectronics and Advanced Materials - Rapid Communications, 11, 11-12, November-December 2017, pp.608-615 (2017).
Submitted at: March 17, 2017
Accepted at: Nov. 28, 2017