Research On Metasurface Coupled Transport And Bound State In Continuum

The sixth generation(6G)wireless communication network has many advantages,such as high communication efficiency,excellent intelligence level and security stability,so as the main band of its communication-terahertz(THz)band has been widely studied in recent ten years.Terahertz spectroscopy,imaging technology has developed dramatically in the past decades,which is due to its promising applications in explosive detection,biology/medicine,wireless communication,etc.Terahertz devices are the best carrier for the development of terahertz technology.Many terahertz devices show capabilities that traditional devices do not have.However,many devices are bulky,complex to manufacture,and have low quality factor(Q value).Therefore,it is extremely necessary to find high-performance,high-quality,and compact terahertz devices.The emergence of metasurfaces provides a good solution to realize the miniaturization and integration of terahertz devices and improve the quality factor of devices.Metasurface is the two-dimensional counterpart of metamaterials,which are easier to manufacture and utilize and exhibit amazing ability to manipulate in front of electromagnetic waves.In this paper,two applications of terahertz metasurface devices are mainly studied by utilizing the properties and capabilities of metasurface,respectively corresponding to the problem of achieving terahertz device miniaturization and high quality factor.The first: Terahertz metasurface plasma waveguide.The coupling and transmission characteristics of terahertz surface waves of Spoof SPPs are studied by means of metasurface metal pore structure.The transmission constraints of terahertz surface waves and the difficult coupling between terahertz signals and micrometer scale plasma waveguides are solved.The second: Terahertz metasurfaces of metal split ring resonators with bound state in the continuum.The BIC metasurface structure is designed in the terahertz band through the SRR structure.The very narrow line width of the BIC can make the terahertz device have the characteristics of high Q value.In the experiment,the corresponding metasurface structures were fabricated on the silicon substrate by using the Lift off technology in the micro and nano processing technology,laser maskless lithography and electron beam evaporation coating equipment.