The Analysis Of Electromagnetic Properties Of Graphene In The Terahertz Range By Method Of Moments

With the rapid development of communication technology,terahertz technology has attracted more and more attention from researchers.Terahertz technology has a bright application prospect because of its many advantages such as wide bandwidth,large capacity of information transmission and high speed.As a carrier of terahertz technology,graphene has unique electromagnetic properties compared with other nanomaterials.Based on the application and development demand of graphene in terahertz technology,the analysis of the electromagnetic scattering characteristics of graphene in terahertz frequency by method of moments are presented.The dispersion characteristics of graphene are the basis of the research.The Kubo formula shows that the surface conductivity of graphene is affected by the intra-band and inter-band transmission characteristics.In this thesis,the conductivity of graphene is firstly calculated by Kubo formula,and the variation of the intra-and inter-band conductivity of graphene in the terahertz band is analyzed.Then according to the conductivity,the surface impedance of graphene is solved.By modeling the dispersive characteristics of graphene accurately,the surface integral equation is established according to the boundary condition of the surface impedance of graphene,and the integral equation is solved by the method of moments.The RWG basis function is used to discretize the integral equation.When calculating the impedance matrix element,due to the existence of the Green's function,it is necessary to do some special processings on the singularity.Finally,the surface induced current of graphene is solved.After a series of post-processing,the scattering characteristics of graphene are obtained.The results are compared with the simulation results to verify the correctness of the frequency domain results.Then,frequency band scattering properties of graphene are converted to the time domain by the Inverse Fourier transform.The results of time domain far-field scattering are obtained,compared with the results of the time domain integral equation method,it proves that the method of this thesis is correct.