三维有序光子晶体红外特性仿真研究OA

The work aims to systematically report the mid-and far-infrared characteristics of three-dimensional ordered photonic crystals,so as to facilitate their subsequent application in infrared stealth and address the issue that the widely used low-emissivity metal coating for evading infrared detection is highly reflective,which is not conducive to multi-band compatibility in visible light,infrared,and radar stealth. The matrix transmission method was adopted to carry out simulation calculation through the visualization calculation software"translight".Since conventionally self-assembled styrene photonic crystals exhibited a face-centered cubic(FCC)structure,the theoretical model was designed with an FCC lattice configuration.Simulations were performed by modifying the following parameters:unit cell dimensions,coating stacking thickness,dielectric constant,incident light angle,etc.The simulation template could be selected from the USE Predefined System.The working band of 3-5 μm was taken as an example to conduct simulation.The primary materials selected were SiO2 and TiO2.For the opal-structured photonic crystals,a 16-layer configuration was required in the simulation,while the inverse opal photonic crystals necessitated 64-layer simulations.In the opal structures,microsphere diameters of 2 μm were selected for simulation design.For the inverse opal structures,air sphere diameters of 1.2 μm,1.6 μm,and 2 μm were simulated.The incidence angles were also studied from 0° to 90°. It was found that the photonic band gap of an opal structure was significantly smaller than that of an inverse opal structure in coatings of the same thickness.Therefore,it was preferable to choose the inverse opal structure for low-emissivity coatings.Besides,the band gap and its central point value increased with the increase of the opal microsphere size or the refractive index of the material.With the increase of the coating thickness,the reflectance of the material increased gradually,and the center point shifted blue.By studying the characteristics of inverse opal photonic crystals under different polarization modes,it was discovered that these crystals exhibited a complete band gap.After the formation of the band gap,the band gap and its central point value did not change.The reflectance of inverse opal photonic crystals was high and the band gap was wide for different microsphere sizes in the working band of 3-5 μm,when the incident angle(>45°)was large. The high consistency between the center wavelength of the band gap in the simulation model and the calculated results from the Bragg equation demonstrates the high reliability of the model.It is also demonstrated through comparison between experimental and literature results that the lower the refractive index of the photonic crystal substrate,the less noticeable the infrared performance.Additionally,by clarifying the optical properties of three-dimensionally ordered photonic crystals in the mid-to far-infrared range,optimizing engineered band gap structures can suppress and shield object radiation while maintaining multi-band compatibility.