Ultra-Wide Band Terahertz Filter using Dendritic Cell-Cluster Metasurfaces

In this paper, we have proposed an ultra-wideband filtering structure based on dendritic Cell-Cluster Metasurfaces in THz regime. The proposed structure consists of Metal-Dielectric-Metal (MDM) array which consists of a dendritic cell to enhance the bandwidth due to multiple resonances. The basic dendritic structure consists of a rod which is split into four rods in the first step. Each split rod is further split into 3 rods. The procedure of splitting is done three times. Numerical simulation results reveal that the proposed structure performs wideband filtering from 2.15 THz to 3.46 THz with transmission efficiency better than 77% at the centre frequency and better than 94% and 86% at band edges. Physical mechanisms involved in broadband filtering characteristics were thoroughly considered. Compared to previous designs, the proposed filter is widest and has the highest transmission efficiency. Such filters have potential applications in THz communication, imaging and astronomical observation systems.