Study On The Transmission Characteristics Of One-dimensional Graphene Photonic Crystals

Photonic band gap and optical localization are the unique properties of photonic crystals(PCs).Artificial introduction of defects or structural adjustment can realize the transformation of photonic band gap and ultimately realize the modulation of electromagnetic wave,which makes photonic crystals have the potential to replace semiconductor sites in the future.Compared with electronic transmission,photon transmission has the advantages of higher transmission rate,faster response speed,larger information storage capacity and lower energy loss,which is exactly what the modern information development is eager for.Although the structure of one-dimensional photonic crystal is relatively simple,it still has the typical characteristics of photonic crystal.Compared with two-dimensional and three-dimensional photonic crystal,one-dimensional photonic crystal calculation is more simple.The work of this paper is based on this model,in order to explore the practical value of one-dimensional photonic crystal.Based on the theory of electromagnetic wave,this paper deduces the transmission matrix of photonic crystal.The transfer matrix method is the calculation method of photonic crystal used in this paper.This method is convenient and fast,and is more suitable for the calculation of one-dimensional photonic crystal.In this paper,three kinds of one-dimensional photonic crystals with different structures are constructed,and the effects of incident angle,period number and period thickness on the transmission characteristics of one-dimensional photonic crystals are analyzed.The results show that the width and position of the forbidden band can be effectively controlled by changing some parameters of the photonic crystal,and the defect mode can also be adjusted to realize the modulation of the transmitted electromagnetic wave.Graphene has many excellent material properties due to its special lattice structure,such as high electron mobility,strong ductility,fast response and so on.However,the low absorbance of single-layer graphene limits its application in photoelectric field.In order to further improve the absorptivity of graphene,this paper applies graphene materials to photonic crystals,proposes a structure model of graphene photonic crystals,and analyzes the corresponding parameters to explore the best optical absorption properties of graphene photonic crystals.The results show that by changing the incident angle,the number of graphene layers and the thickness of defect layer,the graphene photonic crystal can be optimized The absorption band is selected.The optical absorptivity of graphene photonic crystals can also be increased by properly adjusting the structural parameters of photonic crystals.Two kinds of structure models of composite photonic crystals are designed.One is to realize ultra wide reflection band structure in visible light band by superposition of forbidden band,and the other is graphene photonic crystal structure composed of multiple micro cavity defects.This structure improves the light absorption of graphene again.These two structures further improve the practicability of photonic crystals.The research in this paper provides a theoretical basis for the application of photonic crystal to realize light absorption and filtering,and provides a certain reference value in the design of photonic crystal model structure.