Study Of Tunable Terahertz Plasmonic Absorber Based On InSb

Terahertz Science and technology has developed rapidly in recent ten years,and more and more researchers attention,because it is in such as biological science,medical imaging,security and space science,sensor and other fields have important applications.In view of the potential application value and broad development prospects of terahertz technology,it attracts the interest of a large number of scientific research personnel all over the world,and a series of terahertz devices have been developed rapidly.For example,the transmitter,modulator,filter,detector and absorber,etc.,these devices continue to improve the performance of the terahertz system has been continuously optimized.In these devices,the terahertz absorber promotes the further development of terahertz detectors,thermal emitters,sensors and stealth at room temperature.In the past ten years,terahertz absorber based on planar metamaterial has been the rapid development of the terahertz absorber exhibits many excellent properties,such as polarization insensitive,full angle,dual wavelength,three wavelength,ultra narrowband and broadband absorption etc..Unfortunately,the absorption peak is difficult unless the absorber tuning,changing the geometrical parameters for the device,modify its geometry size is awkward.In addition to these so-called super materials are formed by metal and dielectric combination,the arrangement also has certain rules,sometimes want to find the right the metal medium consisting of metamaterials is still quite difficult,so the nature of existence can absorb THz wave,and the dielectric constant of tunable materials?The answer is yes.This paper mainly designed and studied a variety of semiconductor InSb based on tunable terahertz THz absorber,focused on the use of strong coupling electromagnetic induction principle and light transparent cavity leads to physical phenomena happen to split the original resonant frequency tunable multi wavelength THz absorber design.The main innovations are as follows:1.three kinds of materials(metal,graphene and semiconductor)that support SPP wave are compared,and some micro photonic devices with excellent performances are designed by using three materials respectively.2.a single wave length terahertz absorber based on symmetrical T type InSb array has been designed.The absorption efficiency is up to 99.3%.In addition,the position of the absorption frequency can be controlled by temperature.3.analysis of electromagnetic induction in InSb-Air-InSb waveguide transparency(EIT)phenomenon,and design a multi wavelength THz absorber by using this principle,and when the two cavity FP distance to meet the specific conditions,the dual wavelength THz absorber can evolve into a broadband THz absorber.4.it is found that the strong coupling between the light and dark resonator can make the original resonance frequency split into two super resonant frequencies.Based on this principle,an adjustable multi wavelength terahertz absorber based on InSb is designed and studied.5.broadband terahertz absorber(absorption bandwidth is about 0.2THz)and narrow band terahertz absorber(absorbed half full bandwidth is about 0.018THz)are designed by using the FP cavity cascade and the higher order resonance of the FP cavity respectively.Because of the temperature sensitive characteristics of the dielectric constant of InSb,the position of the absorption frequency of the terahertz absorber designed in this paper can be adjusted by temperature.The research work of this paper has potential application value in military field,biological medicine,energy field and so on.