Slow Light Properties Research In Hybrid Photonic Crystals

All-optical network is the future developing trend of communication technology,and the optical cache technology is the key to achieve all-optical communication.Photonic crystals are characterized by micro-structure,flexible design,room temperature operation,optical frequency control and so on.It shows significant advantage in the realization of slow light.In recent years,the study of traditional photonic crystals has become more and more mature.In order to keep the slow light characteristics and further reduce the slow light group speed,the new photonic crystal structure has gradually become a hot spot.In this paper,we focused on the design of hybrid photonic crystals,then studied the structure's slow light characteristics and its application in optical buffering.Firstly,we reviewed and summarized the history of photonic crystals and some related researches at home and abroad.The concept,basic characteristics,practical application and preparation method of photonic crystal are introduced.The contents provide a theoretical basis for the following.Secondly,this part introduces the concept,principle and generation technology of slow light.When referring to how to generate slow light by photonic crystals,several numerical analysis method are studied.We focus on the plane wave expansion method and finite difference method in time domain.The complete two-dimensional photonic crystal structure is taken as an example,and two methods are used to solve the photonic crystal.The specific implementation steps of the band distribution are given in this paper.If defects are introduced in complete structure of photonic crystals,the structures would be line defect optical waveguide and photonic crystal coupling cavity structure.The influence of photonic crystal structure parameters on its slow light characteristics is analyzedFinally,A composite-structure slow light photonic crystal coupled-cavity waveguide is designed by square scatterers and oval scatterers.It is based on structure of triangular lattice photonic crystal.Slow light properties of the structure are studied by using plane wave expansion method.The results show that properties can be optimized by changing the long axis and short axis of the oval scatterers in defect line.The group velocity can be further decreased when the short axis Rb is changed.In this paper,by changing the scatterers composed of the coupled-cavity on both side of infect line,the velocity keeps decreased and the dispersion stays at a low level.When the structure is used as an optical buffer,we made a study on its ache-capacity.