We proposed a multifunctional terahertz metasurface based on a double L-shaped pattern and a vanadium dioxide(VO_(2)) film separated by polyimide.When the VO_(2)film is an insulator,a dual-band electromagnetically ind...We proposed a multifunctional terahertz metasurface based on a double L-shaped pattern and a vanadium dioxide(VO_(2)) film separated by polyimide.When the VO_(2)film is an insulator,a dual-band electromagnetically induced transparency effect is obtained,and the physical mechanism is investigated based on the current distribution and "two-particle" model.When the VO_(2)film is a metal,a dual-band linear-to-circular polarization converter,in which the y-polarized linear wave can be effectively converted to left-handed circularly polarized(LCP) and right-handed circularly polarized simultaneously in different bands,can be achieved.By arranging the metal pattern rotating 30°,a multifunctional antenna can be obtained.When the VO_(2)is an insulator,the radiation of the LCP wave is divided into four beams,with two beams reflected and two beams transmitted.When the VO_(2)is in the metallic state,we can only get the co-polarized reflected wave with a 21° angle.Moreover,in our design,the VO_(2)film does not need lithography to obtain certain patterns,which improves the convenience of fabrication and experiment.Our design opens a new way for the development of multifunctional terahertz devices and has potential applications in the terahertz communication field.展开更多
The complex band structures of a 1D anisotropic graphene photonic crystal are investigated, and the dispersion relations are confirmed using the transfer matrix method and simulation of commercial software. It is foun...The complex band structures of a 1D anisotropic graphene photonic crystal are investigated, and the dispersion relations are confirmed using the transfer matrix method and simulation of commercial software. It is found that the result of using effective medium theory can fit the derived dispersion curves in the low wave vector.Transmission, absorption, and reflection at oblique incident angles are studied for the structure, respectively.Omni-gaps exist for angles as high as 80° for two polarizations. Physical mechanisms of the tunable dispersion and transmission are explained by the permittivity of graphene and the effective permittivity of the multilayerstructure.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 62175016, 61875017, and 61871419)Fundamental Research Funds for the Central Universities (No. 2020RC02)+1 种基金Shenzhen Science and Technology Plan Basic Research Project (No. JCYJ20180305164708625)BUPT Excellent PhD Students Foundation (No. CX2020110)
文摘We proposed a multifunctional terahertz metasurface based on a double L-shaped pattern and a vanadium dioxide(VO_(2)) film separated by polyimide.When the VO_(2)film is an insulator,a dual-band electromagnetically induced transparency effect is obtained,and the physical mechanism is investigated based on the current distribution and "two-particle" model.When the VO_(2)film is a metal,a dual-band linear-to-circular polarization converter,in which the y-polarized linear wave can be effectively converted to left-handed circularly polarized(LCP) and right-handed circularly polarized simultaneously in different bands,can be achieved.By arranging the metal pattern rotating 30°,a multifunctional antenna can be obtained.When the VO_(2)is an insulator,the radiation of the LCP wave is divided into four beams,with two beams reflected and two beams transmitted.When the VO_(2)is in the metallic state,we can only get the co-polarized reflected wave with a 21° angle.Moreover,in our design,the VO_(2)film does not need lithography to obtain certain patterns,which improves the convenience of fabrication and experiment.Our design opens a new way for the development of multifunctional terahertz devices and has potential applications in the terahertz communication field.
基金National Natural Science Foundation of China(NSFC)(61107030)Fundamental Research Funds for the Central Universities of ChinaOpening Foundation of the State Key Laboratory of Millimeter Waves(K201703)
文摘The complex band structures of a 1D anisotropic graphene photonic crystal are investigated, and the dispersion relations are confirmed using the transfer matrix method and simulation of commercial software. It is found that the result of using effective medium theory can fit the derived dispersion curves in the low wave vector.Transmission, absorption, and reflection at oblique incident angles are studied for the structure, respectively.Omni-gaps exist for angles as high as 80° for two polarizations. Physical mechanisms of the tunable dispersion and transmission are explained by the permittivity of graphene and the effective permittivity of the multilayerstructure.
