Asymmetric-Structure Modification of Terahertz All-Dielectric Metamaterial for Electromagnetically Induced Transparency Analogue with High-Quality Factor

An all-dielectric metamaterial (ADMM) based on asymmetric split-ring resonator (A-SRR) is proposed and numerically demonstrated in the terahertz range. The coupling between a bright mode supported by the silicon bars and a dark mode supported by the A-SRR leads to an analogue of electromagnetically induced transparency (EIT). By simply modifying the symmetric SRR into the asymmetric structure, the quality factor of the EIT peak can significantly increase from 255 to 1410, exhibiting a better slow-light performance. This work gives a new way to adjust the asymmetry of the ADMM for higher quality factor, which is useful for applications in slow-light devices and chemical/biological sensors.