Tunable Electromagnetically Induced Transparency in a Metal-Perovskite Hybrid Metamaterial and Its Sensing Performance

Abstract

A metal-perovskite hybrid metamaterial, comprising a gold cross and two gold arcs, is proposed. An electromagnetically induced transparency (EIT) based on bright–bright coupling model leads to a transparent window at 0.75 THz. A multipole scattering theory indicates that the EIT effect is generated by the destructive interference between the electric dipole and the toroidal dipole. By tuning the conductivity of perovskite, the EIT effect is dynamically controlled and shows the modulation depth of 34% at 0.75 THz. Moreover, the theoretical results calculated by the two-particle model are in good agreement with the simulated results. The group delay of the proposed EIT metamaterial can also be dynamically tuned and the maximum value of group delay is 3.53 ps. The sensitivity of the proposed EIT metamaterial is 0.182 THz/RIU. Compared with other sensors, our EIT metamaterial shows excellent sensitivity in the terahertz band. Our work provides a novel method for tunable EIT metamaterials and shows a great practical application value of modulators, slow light devices, and sensors.