Far-infrared Enhanced Absorption Structure Design Based On Surface Plasmon

Surface Plasmon Polaritons(SPPs)is a phenomenon that oscillation of the surface charge density is induced by the interaction between the free electrons on the metal surface and the electromagnetic field of light.When the frequency of the incident light and the frequency of surface plasmon resonance are the same,the coupling action between the charge oscillation and the light field will produce Surface Plasmon Resonance(SPR).Due to unique electromagnetic properties of the surface plasmon polaritons,surface plasmon polaritons has become a hot research subject which has broad application foreground.The far-infrared enhanced absorption structure based on the surface plasmon can greatly improve the absorption efficiency of the infrared device in far-infrared wave band.At the same time,the structure can be changed to adjust the position of the absorption peak,and adjust the full width at half maximum of the absorption peak at specific wavelengths to meet the different needs of infrared devices.It lays the foundation for mature military and civilian use of infrared absorption devices research.In this thesis,a far-infrared wave band enhanced absorption structure is designed based on the surface plasmon polaritons effect.In this thesis,we have established two enhanced absorption structure models that are made up of the gold grating/single or double dielectric layer.The infrared absorption rate of the model is simulated by the simulation software.We analyze infrared absorption characteristics and rules of the enhanced absorption structure by tuning the parameters of gold grating and double dielectric layer,then we get the parameter range of the optimal absorption rate and absorption curve.Finally,we make a comparison between this model and another model which is made up of the metal grating/single dielectric layer,then we summarize the advantages and disadvantages of two different structures models.Based on the simulation,we design the micro-nano processing procedure of the far-infrared enhanced absorption structure unit.We focus on the micro-nano processing procedure of the gold grating/double dielectric layer structure.We analyze several different processing procedures of micro-nano grating structures.Combined with the simulation parameter range,we choose the suitable micro-nano processing procedure.Finally we preliminarily process the enhanced absorption structure unit combined with the actual processing materials and micro-nano processing equipment,and we summarize the results of micro-nano processing.