Design and measurement of a single-dual-band tunable metamaterial absorber in the terahertz band

In this paper, a single-band tunable metamaterial absorber with metal disk array is verified in Terahertz (THz) range. An absorption peak Is achieved based on local surface plasmon (LSP) mode resonance at 14.3 THz with 90% amplitude under room temperature. In the first stage of measurement, this absorption peak is enhanced and shifted to lower frequencies with diameter increasing, while reduced and shifted to higher frequencies with lattice constant increasing. In the second stage of measurement, this peak is in sensitive to temperature. Moreover, a new absorption peak is achieved at 26.6 THz with temperature increasing. This peak is enhanced from 45% to 81% when temperature is increased from 300 k to 400 k, and shifted from 26.6 THz to 18.7 THz. Therefore, a metamaterial absorber that can both modulate new absorption peak and retain original absorption performance is verified.