Design of Metasurface Absorber and Polarizer With Pixelated Approach

In this paper, a pixel-based meta-atom approach is used to demonstrate the absorption and linear polarisation conversion of a terahertz wave by a metasurface. The number of pixels (
$N_{p}$
) in the meta-atom is an integral part of how the metasurface behaves like an absorber and polarizer. By changing the number of pixels both absorption and liner-polarization conversion of a pixelated-based metasurface can be controlled. Pixels positioned diagonally exhibit linear polarisation conversion whereas absorptance is observed if the number of pixels is large. With a decrease in
$N_{P}$
, the bandwidth of polarisation conversion changes from broader to narrower. The physics of absorption and polarisation conversion have been investigated using electromagnetic resonances. The pixelated meta-atom approach can be used for a wide range of terahertz applications.