Terahertz Refractive Index Sensing using Metamaterial Absorber

Metamaterial absorbers are attracted many researchers around the globe for sensing and imaging applications. In bioelectronics, they can be used to sense the change in the refractive index of the surrounding medium and thus be able to detect any prevalent abnormalities. This paper proposes a novel design of such a refractive index sensor based on a metamaterial absorber. The proposed sensor is designed with concentric square and circular gold rings on a polyimide substrate. The absorption rate is 99.88%, with a quality factor of 179.95. The sensor is thus highly operative with a sensitivity of 1.45 THz/RIU and a corresponding Figure of Merit (FOM) 161.11/RIU. The model hence ensures wide applications in designing future sensitive internet of things (IoT) sensors.