On-Chip GaAs-Based Spoof Surface Plasmon Polaritons at Millimeter-Wave Regime

In this letter, a GaAs-based wideband spoof surface plasmon polariton (SSPP) waveguide with super compact size is presented at millimeter-wave regime. The periodic SSPP unit cell consists of a longitudinal slot and a meander slot in transversal direction, and its corresponding waveguide has good low-pass filtering feature. The momentum of microstrip line for measurement feeding to the SSPPs can be well matched without any gradient transition structures. To apply this SSPP waveguide into the design of bandpass filter (BPF), a row of vias is added with a certain distance from the SSPP unit cells. For demonstration, two on-chip examples, i.e., SSPP waveguide and SSPP-based BPF, are fabricated operating at different frequencies. Good agreement between simulations and measurements validates the propagation characteristics and implementation of the proposed SSPPs.