(a) Calculated and (b) measured transmission spectra of the hybrid metasurface with metallic “butterfly”-like pattern by changing the sheet resistance from 400 to 1600 Ωsq⁻¹, the external bias voltage changes from 0 to 4 V in experiments. The inset in (a) shows the schematic of the “butterfly”-like structure and the inset in (b) shows a fabricated sample. The geometric parameters are: L = 7.3 mm, W = 7 mm, g = 1.3 mm, and d = 2.75 mm.