Tunable Terahertz Metamaterials Based on Anapole Excitation with Graphene for Reconfigurable Sensors

Anapole mode is excited by the destructive interference between the toroidal- and electric-dipole moments, resulting in a high-quality (Q) factor. In this paper, we designed a high-Q-factor metamaterial that shows anapole behaviors in the terahertz region. Through the introduction of graphene, the destructive interference condition is disturbed and tunability can be realized. This pattern reflects a brilliant tunability performance in which frequency movements above 250 GHz per 0.1 eV can be verified. Ingenious adjustment by the position of graphene offers the possibility of diversified tuning capabilities. Such a tunable terahertz metamaterial has great potential in reconfigurable sensors.