Active modulation of metamaterial transport properties in the terahertz range

Electromagnetically induced transparency (EIT) effect opens up a vast space for the development of new optical devices, such as slow light units, biological or chemical sensors, and nonlinear devices. In particular, the active control of EIT in metamaterials offers fascinating prospects for improving optical networks, 6G/terahertz communications, active sensor. Here, a all-dielectric metamaterial based on EIT effect is proposed and verified. A transmission window with 85.6% of amplitude is achieved at 14.2 THz. The amplitude and resonant frequency of the transmission window can be controllably switched by an active modulation method. At the same time, the group delay of this metamaterial sample is also actively switchable. The frequency selectivity of this metamaterial sample can also be achieved by changing the diameter of the silicon array. Finally, the metamaterial sample is immersed in oil with different refractive indices. The resonant frequency of the transmission window is moved to low frequency as the refractive index of oil increases. The metamaterial sample has the potential to be used in light buffing, 6G/terahertz communications, and ultrafast devices.