Compact and highly-confined spoof surface plasmon polaritons with fence-shaped grooves

In this paper, a compact and highly-confined spoof surface plasmon polaritons (SSPPs) with fence-shaped grooves is proposed. By adding the metal strips that similar to the fence on the basis of T-grooves, the waves can be confined more tightly as the propagation paths of current are effectively increased, which leads to a reduction of the height of SSPPs units by 48.4% compared to the rectangular grooves. Moreover, compared with conventional SSPPs units mentioned before, the proposed design exhibits the strongest confinement to EM waves. To verify the effectiveness of the proposed unit, a corresponding transmission line is simulated and fabricated. Both simulated and measured results are in good agreement, which show the superior performance of this structure. Meanwhile, due to the simplicity and effectiveness, this proposed structure has a great research and application prospects in developing the miniaturized devices and circuits.