Ultrafast Frequency Shift of Electromagnetically Induced Transparency in Terahertz Metaphotonic Devices

Recently, the actively controlled meta‐atoms have been employed to manipulate terahertz (THz) waves allowing for the implementation of many functionalities operating. A salient example of such systems is the electromagnetically induced transparency (EIT) metaphotonic device, which opens up a new avenue for THz manipulations. However, these devices are currently limited to be tuned at a given frequency, which severely impedes their practical applications. Here, novel photo‐active THz meta‐atoms are proposed, whose EIT resonance is equipped with a frequency tuning functionality up to 36%. At different levels of optical pumping power, a substantial modulation of EIT resonance is realized at the fundamental and shifted frequency, respectively. Moreover, the ultrafast dynamics manifest the switching time scale of ≈1 ns. This configuration is easily extensible by other types of stimuli, which may contribute to the development of multifunctional active tuning meta‐photonic systems.