Line Defect Photonic Crystal Waveguide Dispersion Properties Are Analyzed

Photonic crystal (PC) is a new optical micro-structure which is periodically constructed by materials with different dielectric constants. It shows the points array structure with light-wave level in one to three dimensions space. PC has unique light-guiding principle and many peculiar optical properties, so the theory and application research of PC is very active. In recent teenyears, PC is from original academic idea to practical application domain. Presently, the researching of PC has become the most advanced and hottest project in optoelectronic field.The main work of this paper is the analysis of dispersion property with photonic crystal waveguides. Because PC has unique nonlinear effects, and furthermore, all of these effects are concerned with dispersion closely. PC can be used to make compact devices for highly efficient dispersion compensation, so that it has great application potential for optical fiber communication systems.In this paper, initial introduction about the concept, research status quo and application domain of PC, then the energy band theory has been discussed, which is the fundament about PC research. The research of PC need to use multiplicate numerical methods. Two most commonly used methods——plane-wave expansion method (PWE) and the time-domain finite difference method (FDTD) are compared and their numerical arithmetic are analyzed respectively. Based on the advantages & disadvantages of two method, the idea that analyzing band gap by PWE and analyzing dispersion property by FDTD is put forward.In Chapter 4, the sharp dispersion of supermodes caused by modes interaction under "anti-crossing" effect is investigated. Making use of the corresponding results of analysis and calculation, the structure of PC waveguide can be designed, and with FDTD, the dispersion coefficients of supermodes have been calculated as our structure model. In addition, we draw the dispersion curves in certain frequency domain. The results show the crystal lattice and several structure parameters, as air hole diameter and relative aperture, all of these can influence dispersion. Through designing the structure parameters we can engineer the chromatic dispersion of waveguide. These results have practical function to direct waveguide designing.About experiment work we cooperated with relative graduate school in making PC fibers. We have obtained materials for testing and designed the experiment plan. The further work can make use of these conditions.