Nano-printing technology based double-spiral terahertz tunable metasurface

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 ofterahertz waves in the fields of communication and imaging. We design and prepare a flexible and transparentdouble spiral metasurface based on nano-printing technology, and use the metasurface to construct a rotatingtunable filter, which can achieve regular tuning of the terahertz wave transmittance by rotating themetasurface. After rotating 90 degrees, the transmittance at 0.52 THz increases from 8% to 67%, and thetransmittance at 0.92 THz decreases from 68% to 3%, thus realizing active tuning with modulation depthgreater 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 andlarge-area preparation of terahertz tunable devices.