Graphene Metasurface-Based Tunable Polarization Filter for Terahertz Application

This article presents a graphene metasurface-based polarization filter for filtering random or unpolarized light and polarization conversion of random or unpolarized light. The presented polarization filter operates in the far-infrared, terahertz frequency regime. The resonant frequency of the presented polarization filter is tunable over a broad spectrum of 2.3 terahertz which lies between 2 terahertz to 4.3 terahertz. The tunable resonant frequency is achieved by using graphene as the material for the construction of the metasurface. Numerical simulations of the proposed model displayed results that verify that the presented polarization filter has a very high efficiency as it shows approximately 0 absorption of the filtered light. The angle stability response of the proposed polarization filter has also been investigated which verifies that the presented filter can find potential applications such as polarization conversion and optical modulation of unpolarized light.