Research On Absorption Characteristics Of Biological Photonic Crystals Based On Graphene Defects

At present,the majority of current designs focus on building an elaborate metallic pattern on a thin dielectric spacer film,which attach to a thick metal layer.It is worth noting that most reported absorber designs contain miniature and elaborate structural features,and then it is setting manufacturing obstacles for the practical applications of super absorbers.The emergence of the graphene,is considered to be a promising material for realization of ultra-fast optoelectronic devices,and may lead to materials revolution in other fimctional materials and many other fields.In recent years,the research and application of graphene covers a wide range of fields,and the research and application of graphene covers a wide range of fields.Due to the excellent nonlinear properties,absorption properties of metals and wide band adjustment,graphene is used to design an absorbing device instead of metal layer.The introduction of graphene i5 devoted to study the variation of the absorption characteristics,and design one-dimensional photonic crystal structure with dual band absorption.Graphene layers have a significant effect on the absorption.Currently,the study of dual-band and multi-band absorption is lesser.In this paper,dual-band absorption can be realized by engineering an asymmetric one-dimensional photonic crystals(1DPC)with a defect based on graphene.The dual-band absorption characteristics of one-dimensional photonic crystals with graphene-based defect were theoretically analyzed and numerically simulated using the transfer matrix method(TMM).The dependence of dual-band absorption characteristics on period number M of the structure behind the graphene layer,graphene layers,dielectric thickness of defect layer,and the incident angle are obtained.Simulation results show that the absorptions with the lights with wavelength 699nm and 1000nm approximately are enhanced with the increasing of the layers of graphene.The absorption peaks increase with the decreasing of the dielectric thickness of defect layer and move toward the shorter wavelength.In the TE mode,the absorption peak can be regularly tuned by varying the incident angle.In this paper,the 1DPC engineered saves raw material to a eertain degree,and the preparation process i5 simpler due to the smaller total thiekness and is convenient for application in a variety of absorbers.In addition,the number and position of absorption peaks can be adjusted by changing the dielectric thickness and defective media.This paper provides the theoretical basis for the study of graphene absorbers,and the designing concept for its application.Most absorption devices are reciprocal,at present.The absorption rate of the absorption material is independent to the incident direction.Along with the research of optically active materials gradually coming,the magneto-optical effect(the effect on the interaction of magnetic field on light and medium)is applied to nonreciprocal transmission device.The dielectric constant or permeability of magnetooptical materials is non-diagonal element,which destroys the time reversal symmetry.In order to achieve the nonreciprocal transmission,the inversion symmetry of the space must be destroyed at the same time.This paper adds the magneto-optical material into the multilayer composite membrane,and the effects of the time reversal symmetry and the spatial inversion symmetry on the nonreciprocal transmission of the structure are compared,and then at last finds the best structure.By changing the parameters of the magneto-optical material,the effect on the absorption and the nonreciprocal transmission of the structure are studied.The addition of the magneto-optical material,achieve the goal of the nonreciprocal transmission,and the two direction of the structure will be both used rationally.