Ultra-broadband multilayer absorber with the lumped resistors and solid-state plasma

Abstract

In this paper, an ultra-broadband multilayer tunable absorber (MTA) with the lumped resistors (LRs) is proposed, where a dielectric layer is sandwiched between three split square ring resonators and a continuous metallic plane. It is noted that two truncated triangular ring-shaped and Y-shaped solid-state plasma resonators (SSPRs) are embedded in the substrate. Three solid-state plasma cylinders are also inserted between the truncated triangular ring-shaped resonators and Y-shaped SSPRs. External two split square rings and a truncated triangular ring are loaded with the lumped elements. After calculation, for the TE wave, the absorption rate is larger than 90% in a certain frequency region which covers 7–16.25 GHz. Moreover, the proposed MTA is polarization independent at normal incidence. The absorption mechanism and properties also are investigated. The obtained results illustrate that the absorption performance and operating frequencies can be tailored when the different SSPRs are excited. Keywords: Absorber, Solid-state plasma, Lumped resistors, Tunable properties