Design And Properties Of Wide Spectrum Infrared Absorption Structures Based On Metamaterials

Infrared ray is also known as infrared radiation.The wavelength range of infrared ray is 0.76～1000μm.which is situated between visible light and microwaves.Metamaterials,however,are periodic structures designed and manufactured by humans.They have different electromagnetic properties,these properties do not exist in nature,such as photonic crystals and left-handed materials.The absorption and control of electromagnetic waves can be realized by adjusting the parameters of metamaterials.This study aims to enhance the absorption performance within the infrared band by combining infrared detection technology with metamaterials.By adjusting the structural parameters of metamaterials,various absorbing structures can be designed to achieve optimal absorption effects.By using the CST STUDIO SUITE（CST）simulation software,the absorption model was built in the simulation space,and the simulation and parameter optimization were carried out.The infrared absorption characteristics of the metamaterial structure of the cross resonant absorber were investigated.The influences of the top width of the cross structure,the thickness of the cross metal layer,the Angle of cross overlap,the thickness of Ge layer and the thickness of silicon nitride（Si₃N₄）on the infrared absorption characteristics were studied.By comparing the absorption characteristics of metamaterial with different parameters,the optimized structural parameters are obtained as follows:periodic element structure size 20μm,cross top width 5μm,surface patterned metal layer thickness 0.05μm,cross overlap Angle 90°,Ge layer thickness0.35μm,Si3N4 layer thickness 0.4μm.The structure can achieve wide spectrum and high absorption of infrared radiation in the wavelength range of 9～13μm.This paper also tries to coupling a variety of combination structures with each other,and the resulting composite structure metamaterial absorber has achieved good results,including cross and limit bar combination structure,cross and square open ring combination structure,disk and limit bar combination structure,etc.These composite structures also achieve high absorption of infrared radiation.By observing the electric field of the composite structure and the single structure,the absorption effect difference between the composite structure and the single structure is analyzed.Finally,the polarization sensitivity and incidence Angle sensitivity of the absorption structure of metamaterial are explored.Finally,a variety of metamaterial absorption structures designed in this paper are prepared and tested,and the design and simulation results described in the previous paper are verified.Also,the different between the test and simulation results is analyzed and discussed from the point of the actual process.