Terahertz High-Q Absorber Based on Holes Array Perforated into a Metallic Slab

In this paper, we theoretically analyze and design a dual-narrowband terahertz (THz) absorber based on a hole array drilled into a metallic slab. A very high-quality factor (Q) is achieved at both of the resonance frequencies. A circuit model-based approach is developed for the analysis and design of the proposed absorber. The absorption peaks occur at 2.46 and 3.75 THz frequencies with 98% and 96% absorptions at normal incidence, respectively. The achieved quality factors are 149 and 144, at 50% absorbance for the two absorption bands, respectively.