Polarization Controlled High Efficiency Color Filters Using Si Nanoantennas

Abstract

Metasurface is a new concept to manipulate the amplitude and phase of the incoming wave locally from the surface. Metasurface is composed of 2D elements so called nanoantennas, which show practical solution for manipulation of light unlike 3D metamaterials devices which are difficult to fabricate at nano scale level. Many of the devices are already designed using the concept of metasurfaces which include meta-lens, vortex plates, holography, and color filters. Color filters designed using metasurfaces attract attention of researchers because of their significant advantages over pigment based printing technology such as high contrast, low power, and ultra-high resolution. Recently, a new trend is emerging to use all dielectric based metasurface filters, which are much more efficient compare to plasmonics color filters. These filters can be easily integrated with existing electronic circuitry, since these filters are designed using Si material. In this work, we propose polarization dependent widely tunable all dielectric color filters, whose basic constitute element is Si based cross shaped nanoantennas. These filters are designed using cross shaped nanoantennas with different arm lengths. Each arm of nanoantenna responds for different state of polarization of incoming light, which results in different color spectra. We illustrate a wide tunability of these filters in visible spectrum with numerical simulation.