The focusing effect of electromagnetic waves in two-dimensional photonic crystals with gradually varying lattice constant

Bakhshi Garmi, F; Barvestani, J

doi:10.18869/acadpub.ijpr.15.4.401

The focusing effect of electromagnetic waves in two-dimensional photonic crystals with gradually varying lattice constant

Authors

F Bakhshi Garmi

J Barvestani

https://doi.org/10.18869/acadpub.ijpr.15.4.401

Abstract

In this paper we studied the focusing effect of electromagnetic wave in the two-dimensional graded photonic crystal consisting of Silicon rods in the air background with gradually varying lattice constant. The results showed that graded photonic crystal can focus wide beams on a narrow area at frequencies near the lower edge of the band gap, where equal frequency contours are not concave. For calculation of photonic band structure and equal frequency contours, we have used plane wave expansion method and revised plane wave expansion method, respectively. The calculation of the electric and magnetic fields was performed by finite difference time domain method.

Keywords

graded photonic crystal

lattice constant

photonic band gap

refractive index

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