Fig. 4: Tunable diffraction with the asymmetric nano-electromechanical metasurface.
a Measured intensity at the Fourier plane of the metasurface as a function of the applied bias from 0 V to 8 V (λ = 1524 nm). At each bias, the intensity is normalized by the peak intensity near 0∘. The ±1st order diffractions start to appear ~±10∘ when the applied bias is over 6 V. On top of the image, the values of V1–V4 are noted and only V4 is changed. b–f Measured diffraction patterns for various configurations of the applied biases (λ = 1524 nm). (top) Normalized intensity images are measured at the Fourier plane of the metasurface. The values of V1–V4 are noted on top of the images. Scale bars are 0.05k0 where k0 is a magnitude of wave vector in free-space. (bottom) Measured cross-sectional intensity profiles are plotted as a function of the diffraction angle. The intensities are normalized by the peak intensity at 0∘. The diffracted signals ~±10∘ are denoted by red shades.
