A polarization tunable incident angle tolerant dielectric metasurface-based color filter

Abstract

We designed and analyzed an ingenious Si–SiO₂–Si dielectric metasurface to obtain structural colorization harnessing the contrast between the refractive indices of dielectrics. Though a few Si-based dielectric metasurfaces were reported, the performances of these metasurfaces were poor. We analyzed the optical properties of the dielectric metasurface employing the finite-difference time-domain (FDTD) technique. Electric field distributions revealed our proposed dielectric metasurface reflected light for a particular polarized light due to the strong light–matter interactions and the asymmetric nature of the structure. We adopted structural parameters by utilizing a parametric sweep method. Our proposed structure can tune a high color difference by varying polarization angles. We achieved a high color difference of ∼68 for the TE-polarized plane wave with negligible optical loss. Amazingly, our proposed dielectric metasurface structure exhibited a color difference of ∼20 for a high angular tolerance of 60°. Our proposed dielectric metasurface structure can benefit diverse applications such as hyperspectral imaging, color filtering, and anti-counterfeiting applications.