Compact Multiway Plasmonic-Power-Splitters with Arbitrary Phase Responses

We propose compact plasmonic-power-splitters with arbitrary phase responses in the millimetre waveband based on spoof surface plasmon polaritons (SSPPs). Benefitting from the strong field confine-ments of SSPPs, the branches of the proposed plasmonic-power-splitters can be flexibly bent to meet the design requirement of various situations, while their transmission performance is nearly not affected. Of note, the output phase responses of the plasmonic-power-splitters can be flexibly controlled by adjusting the SSPP propagation constant of each branch only via optimizing the unit size, without changing the overall layout of the power splitter. At a proof of concept, two eight-way plasmonic-power-splitters with exactly the same layout are designed, simulated and measured. They can achieve eight-way equal out-put powers, but their output phase shifts are 0 & DEG; and 45 & DEG;, respectively, at the center frequency of 26 GHz. We show that the designed power splitters have good power allocation performance in an ultrawideband range from 5 to 30 GHz. Though the phase responses cannot maintain good consistency in such a wide bandwidth, it can be designed at any center frequency in the band. The proposed power splitters show big advantages of path compatibility, high compactness, and customizable phase response, which is promising in large-scale integrated circuits.

Automated summary

This paper proposes compact plasmonic-power-splitters with arbitrary phase responses in the millimetre waveband based on spoof surface plasmon polaritons (SSPPs). The proposed power splitters have the advantages of path compatibility, high compactness, and customizable phase response. They show good power allocation performance in an ultrawideband range, but the phase responses cannot maintain good consistency in such a wide bandwidth.