Optimizing the performance of the CPW-to-spoof surface plasmon polariton waveguides for 0.3 THz band

The competition to suggest high performance solutions for terahertz communication targets 0.22-0.32 THz band because of its bandwidth and attenuation advantages over other terahertz frequencies. However, the state-of-the-art suffers from conventional terahertz waveguide performance. Alternatively, the spoof surface plasmon polariton waveguides (SSPP WGs) measurements achieve the record-low insertion loss per unit length at 0.3 THz. On the other hand, the SSPP WGs require high performance transitions to interface with terahertz active devices such as transistors and diodes. In this paper, we present design, optimization, and experimental verification of high-performance coplanar waveguide-to-SSPP WG (CPW-to-SSPP WG) transitions at 0.25-0.3 THz band. The measurements show that the insertion loss of a CPW to SSPP WG transition can be suppressed up to -0.5 dB at the proposed frequency band.