Analogue of electromagnetically-induced transparency based on magnesium-ferrite metamaterials in the THz regime
The Korean Physical Society, BEXCO BUSAN, Korea (2022)
Tae-Han Kim, Yongbin Bang, Sang Yoon Park and Bo Wha Lee
Abstract
Electromagnetically-induced transparency (EIT) within a wide avsorption profile is due to the quantum destructive interference of two different transition channels in three-level atomic systems. EIT-like effects of metamaterials also arise due to the near-field coupling between adjacent resonators and the estructive interference between bright and dark modes , or between bright and bright modes. The analogy of EIT effect in magnesium-ferrite metamaterials is characterized by employing a 3D finite-difference time-domain (FDTD) simulation. The magnesium-ferrite metamaterials consist of a cross resonator (CR) on the upper side and a disk resonator (DR) on the lower side of polymide substrate, respectively. The analysis of the FDTD simulation revealed the dynamics of electromagnetic field. the near field couplings of CR and DR, and the EIT- like spectral features of our designed magnesium-ferrite metamaterials as functions of the asymmetric parameter and polarization angle.
At the special asymmetric parameter, the group index and the group delay are reached up to 6485 and 238.4 ps at 0.729 THz, respectively. Moreover, the figure of merit of 416 and th Q-factor of 644 are also obtained. These results may give a physical understanding of various potential applications such as slow-light devices, THz sensors, tunable switching, etc. in THz regime.