Index-Tunable Terahertz Metadevices Based on Double-Layered Closed-Ring Resonator Arrays

Abstract

We demonstrate index-tunable metamaterials and metadevices working in the terahertz (THz) frequency range based on double-layered closed-ring resonator (CRR) arrays.The double-layered CRR arrays have a narrow-band transmission peak which shows negative refractive index even in normal incidence. We show that the effective refractive index can be widely tuned by slightly shifting relative position of the arrays. We also demonstrate that THz beam steering can be realized by utilizing the double-layered CRR arrays arranged in a wedge-shaped prism.