Nano-printing technology based double-spiral terahertz tunable metasurface

Abstract

Electromagnetic devices made of artificially constructed metasurfaces can achieve filtering, modulation, sensing, and detection functions in the terahertz frequency band, which is essential for the applications of terahertz waves in the fields of communication and imaging. We design and prepare a flexible and transparent double spiral metasurface based on nano-printing technology, and use the metasurface to construct a rotating tunable filter, which can achieve regular tuning of the terahertz wave transmittance by rotating the metasurface. After rotating 90°, the transmittance at 0.52 THz increases from 8% to 67%, and the transmittance at 0.92 THz decreases from 68% to 3%, thus realizing active tuning with modulation depth greater than 88%. Moreover, the proposed nano-printing metasurfaces have excellent properties of ultra-thinness, flexibility, and visible light transparency, which are conducive to the miniaturization, light-weight and large-area preparation of terahertz tunable devices.