Frequency-tunable circular polarization beam splitter using a graphene-dielectric sub-wavelength film

TL;DR

This paper introduces a graphene/dielectric sub-wavelength structure capable of tunably manipulating circular polarization of light over a broad frequency range, with potential applications in chemistry and biology.

Contribution

A novel graphene/dielectric-stacked structure demonstrating tunable, broad-band circular polarization control using magnetic field and chemical potential adjustments.

Findings

Efficient manipulation of circular polarization over a broad frequency range.

Structure is transparent to one circular polarization and opaque to the other at oblique incidence.

Tuning achieved via magnetic field and graphene chemical potential adjustments.

Abstract

Manipulating the circular polarization of light is of great importance in chemistry and biology, as chiral molecules exhibit different physiological properties when exposed to different circularly polarized waves. Here we suggest a graphene/dielectric-stacked structure, which has both the properties of a epsilon-near-zero material and the high Hall conductivity of graphene. The proposed sub-wavelength structure demonstrates efficient manipulation of circular polarization properties of light. In a quite broad frequency range and at a large oblique incidence angle, the present magnetically active structure is transparent for one circularly polarized wave, and opaque for another. Such an effect can be further tuned by changing the magnitude of the applied magnetic field and chemical potential of graphene.