Design of spoof surface plasmon polaritons based transmission line at terahertz frequency

Abstract

In this paper, we report a plasmonic metamaterial, i.e., spoof surface plasmon polaritons based back to back broadband transition at terahertz frequency. Also we have designed another structure using a unit cell that is made up of by combining three SSPP strip together. This structure shows a way to realize stopband within the operating frequency of spoof surface plasmon polaritons. Using the new type of unit cell disturbs the surface impedance matching and thus gives band stop in the transmission spectrum of SSPP. The first design of transition has reflection coefficient less than −10 dB and transmission loss is less than 5 dB in 0.1–0.8 THz range of frequency. The second designed structure shows strop band from 0.569 to 0.6124 THz and band pass is maintained from 0.1 to 0.569 THz and from 0.6124 to 0.6516 THz. Reflection coefficients in the band-pass region is less than −10 dB and transmission loss is less than 8 dB while in the band stop region reflection coefficient is −3 dB and transmission coefficient is −24 dB has been obtained. Such type structures will show promising application in plasmonic device and systems.