Monday, April 13, 2015
Abstract-A broadband terahertz absorber using multi-layer stacked bars
We present the simulation, implementation, and measurement of a broadband terahertz (THz) absorber. By stacking 12 metallic bars of varying lengths on three polyimide layers with equal spacing, a broadband is formed through merging multiple successive resonance peaks. The measured total exceeds 95% from 0.81 to 1.32 THz at the normal incidence and the full width at half maximum is 64% (from 0.76 to 1.48 THz). The decreases with fluctuations as the incident angle increases but remains above 62% even at the incident angle of 40°. The physical explanation to the mechanism is presented and verified by a 9-bar example, which exhibits narrower bandwidth. It is also experimentally demonstrated that the proposed structure is robust against misalignment of each metallic layer.