Progress of liquid crystal based terahertz wavefront modulators

Liquid crystal, with a broadband external field induced tunability, has obvious application advantages in the terahertz band. It is expected to realize efficient and active terahertz wavefront modulation. This article briefly summarizes some of the recent researches carried out by the group of liquid crystal and micro/nano optics of Nanjing University and other research teams in the field of liquid crystal based terahertz wavefront modulators. There are mainly two types, including pure liquid crystal based modulators and liquid crystal integrated metadevices. The characteristics of the dynamic tunability, diversified functions and potential application prospects of these devices are systematically described. The development trend of the combination of liquid crystal and terahertz technology is also discussed.