Metamaterials With Analogous Electromagnetically Induced Transparency and Related Sensor Designs—A Review

Electromagnetically induced transparency (EIT) originates from quantum physics, where a narrow transparent peak appears in the opaque band due to the destructive interference between quantum states of atoms and molecules. Similar phenomena can be realized based on strong-coupling resonators with a similar spectrum of transmission peaks and abrupt dispersion variations. These classical systems, ranging from elastic to optical, are named analogs of EIT. The sharp resonant peaks with high-quality factors in the spectrum exhibit powerful potentials in sensors with ultrahigh sensitivity. In order to better understand the development history of EIT-like metamaterials and their specific applications in the field of sensors, this article makes a brief review of the EIT-like phenomenon in metamaterials. First, we conduct the universal mathematical formulation based on the coupling oscillator model. Then, we classify specific metamaterial designs and practical applications of EIT-like devices in acoustic, electromagnetic, and optical waves, respectively. We also summarize the recent technologies of dynamic modulations of EIT-like metamaterials and discuss future research directions.