A Four-Port Ultra-Compact Terahertz Splitting Filter Based on Graphene Nanoribbon

Abstract

A four-port ultra-compact plasmonic splitting filter based on graphene diamond ring resonator is proposed and investigated by using the finite-difference time-domain method. Numerical simulation results show that the transmission spectra can be affected by the structural parameters and the chemical potential of graphene. Especially, the resonant frequencies can be easily manipulated by changing bias voltage without changing the dimension parameters of the filter. The simple structure that consists of graphene nanoribbon waveguides and a graphene resonator shows both splitting and filtering capability. This compact intersection structure has potential applications in highly integrated optical circuits for terahertz frequency.