Electric field distribution of photonic crystals waveguide with function line defect

Abstract

In this work, the finite element and supercell methods are used to study the effect of function line defect on the photonic band structure and electric field distribution in a two-dimensional photonic crystals waveguide. We designed to introduce a row of function defect in the photonic crystals waveguide. The transmission characteristics of the photonic crystals waveguides are modulated by adjusting the function coefficient k and parameter b of the dielectric constant of the function defect dielectric column. By changing the structure parameters of the dielectric constant, the radius of the function defect dielectric column and the dielectric constant of the two-dimensional regular photonic crystals dielectric column material, we found that the band gap position, band gap width, defect mode number, defect mode position and defect mode width change. The electric field is well localized at the defect location, but their intensity are different. The three-pole defect mode can be activated, and the defective mode eigenfield distribution is symmetrical. Compared with the two-dimensional regular photonic crystals waveguide, the width of forbidden band becomes wider and the number of defect modes increases. The band gap structure and electric field distribution have the adjustability for the two-dimensional photonic crystals waveguide with function line defect. These results will provide new designed methods and theoretical basis for the related optical devices.