Abstract-Terahertz multi-band unidirectional reflectionless phenomenon in a MIM plasmonic waveguide system based on near-field coupling

Tianyi Dai, Fei Zhao, Cong Zhang, Xing Ri Jin, Ying Qiao Zhang, Chengshou An,  YoungPak Lee

https://www.worldscientific.com/doi/10.1142/S0218863519500085

Dual-band unidirectional reflectionlessness is investigated in a system consisting of three stub resonators side-coupled to a metal-insulator-metal plasmonic waveguide based on near-field coupling in terahertz domain. Reflectivities of ∼0 (∼0.65)$\sim 0(\sim 0.65)$ and ∼0 (∼0.97)$\sim 0(\sim 0.97)$, respectively, at two exceptional points 4.11$$THz and 4.695$$THz are obtained for forward (backward) direction. More than that multi-band unidirectional reflectionlessness is demonstrated based on multi-stub resonators side-coupled to an MIM plasmonic waveguide.