Tailoring multi-order absorptions of a Salisbury screen based on dispersion engineering of spoof surface plasmon polariton

摘要

In this paper, a comprehensive scheme of a Salisbury screen is proposed which makes full use of dispersion engineering of spoof surface plasmon polariton (SSPP) to tailor its multi order absorptions. As a proof, the symmetrical corrugated groove structures made of metal strips are adhered on dielectric grid periodically as plasmonic metamaterial (PM), and then used as a spacer in a Salisbury screen. Owing to the enhanced k-vector as well as nonlinear k-dispersion relationship inspired by PM spacer, the multi-order absorptions of the proposed SSPP Salisbury screen can be adjusted to lower frequency in a nonlinear scale. Simulation and experimental measurement demonstrate that the fundamental and first-order absorptions can be adjusted from 7.5 and 22.5 GHz to 4.7 and 9.0 GHz, and their according frequency ratio is also changed from 1.0:3.0 to 1.0:1.9. The proposed attempt opens a door for further optimization of conventional absorbing structure based on dispersion engineering of SSPP, enabling a wide range of applications.