Terahertz Metamaterial Sensor Based on Electromagnetic Induced Transparency

A graphene-based terahertz electromagnetically induced transparency (EIT) metamaterial sensor is proposed and studied. The sensor is made up of two bright modes: a graphene strip resonator and a 7-shape resonator. In a terahertz metamaterial sensor based on EIT, the metamaterial structure is designed to have two resonant modes that are coupled through a common resonator. When terahertz radiation hits the metamaterial, the two resonant modes interact, creating a window of transparency in the transmission spectrum. It illuminated that the physical mechanism of the EIT effect lay in the recombination effect of the conductive resonators. By changing the carrier relaxation lifetime or the Fermi energy of the graphene, the amplitude or the location of the EIT window could be actively tuned. The terahertz metamaterial sensors based on EIT have the potential to provide highly accurate and sensitive measurements in a wide range of fields and could lead to important advances in medical diagnostics.