Analysis Of Transmission Characteristics Based On Surface Plasmon

Surface Plasmon Polariton(SPP),surface electromagnetic wave confined at the interface between metal and dielectric,attracted a lot of attention recent years,This paper analyzes the propagation characteristics and phenomena of SPP by studying metal electromagnetics,and designs some devices for SPP propagation.The main contents are as follows:(1)In this paper,a subwavelength structure with enhanced light transmission based on phosphorene SPP is designed.Firstly,the conductivity of monolayer phosphorene and the features of phosphorene SPP are studied.Then,a sandwich structure is proposed,with gold nanogratings in the upper layer,phosphorene films in the middle and silicon substrate at the bottom.The enhanced light transmission mechanism of phosphoalene SPP is studied by experiment and discussion,and the transmission spectrum and field distribution of the structure are also analyzed.The results show that the phosphorene SPP can be coupled with more light.Then,the enhanced transmittance can be realized.(2)A hybrid plasmonic waveguide(HPW)with dual-ridge(DR)structure based on Bulk-Dirac-Semimetal(BDS)is proposed.Firstly,the electromagnetic characteristics of BDS are studied,and the SPP modes supported by BDS are obtained according to the model solving theory.It is found that the radiation loss of BDS SPP is great which result to the field of SPP cannot confined on the surface of BDS.Fortunately,by designing HPW based on BDS with terahertz frequency,the effective coupling between BDS SPP mode and dielectric waveguide mode is realized.Then,the radiation loss of BDS SPP is reduced efficiently.Compared with the traditional HPW,the smaller mode area and the longer propagation length can be obtained.In addition,by adjusting the geometric parameters and BDS Fermi energy leve,the minimum mode area of 2 ?m2 and the maximum propagatiol length of?105 ?m are obtained at the frequency of 3 THz.(3)Based on the theory of Spoof Surface P lasmon Polariton(SSPP),a band-stop filter is proposed.The filter is composed of coplanar waveguide(CPW)and SSPP transmission line.The stop-band is formed by coupling the defective unit with CPW,and the frequency of the stop-band can be flexibly adjusted by controlling the length of the defective unit in SSPP transmission line.The simulational results show that the frequency range of the stop-band is 6.5-7.3 GHz,the bandwidth is 0.8 GHz,and the quality factor Q=8.6.In addition,the passband insertion loss is less than 3 dB,the passband reflection is less than-10 dB and the stopband suppression is less than-23 dB.