A tunable metamaterial absorber made by micro-gaps structures

This paper presents a research in tunable metamaterial (MM) absorber. We design an original split ring resonator (SRR) absorber, in first. Then through adding different group micro-gaps and increasing the number of micro-gaps, we investigate the change of different structures. We find the micro-gaps with a larger a, which is the position angle on the SRR, have a greater impact to the absorption characteristics, and the affect of the micro-gaps in low position can be ignored. It can be controlled by MEMS switches in theory. In addition, we also design a dual-band MM absorber combined by two micro-gaps structures, which has 96.04% and 96.68% absorptivity at 8.14GHz and 12.72GHz, respectively. The research is an exploration in tunable MM absorber direction and gives us an effective way to design the multi-band MM absorber.