Continuously tunable and fast-response terahertz metamaterials using in-plane switching dual-frequency liquid crystal cells
Chia-Yi Huang, Chia-Chun Chen, Wei-Fan Chiang, Min-Cheng Tsai, Shun-An Jiang, Tsung-Hao Chang, and Song-Hang Wang
A metamaterial that is embedded into an in-plane switching dual-frequency liquid crystal cell is used to develop an electrically controllable terahertz metamaterial. The resonance peak of the metamaterial can be redshifted and blueshifted as the frequency of an external voltage is switched, and the response times for the redshift and blueshift are 1.044 ms and 1.376 ms, respectively. A simulation confirms the spectral redshift and blueshift. The variation in the peak frequency as a function of applied frequency at the external voltage is presented. Experimental results show that the resonance peak of the metamaterial can be continuously tuned within a frequency range of 15 GHz as the applied frequency is switched between 19 kHz and 22 kHz. Therefore, this metamaterial is a continuously tunable and fast-response terahertz filter and could be used for terahertz imaging and terahertz telecommunications.