We demonstrate an electrically tunable polarizer for terahertz (THz) frequency electromagnetic waves formed from a hybrid graphene-metal metasurface. Broadband (>3 THz) polarization-dependent modulation of THz transmission is demonstrated as a function of the graphene conductivity for various wire grid geometries, each tuned by gating using an overlaid ion gel. We show a strong enhancement of modulation (up to ∼17 times) compared to graphene wire grids in the frequency range of 0.2–2.5 THz upon introduction of the metallic elements. Theoretical calculations, considering both plasmonic coupling and Drude absorption, are in good agreement with our experimental findings.
Engineering and Physical Sciences Research Council (EP/P007449/1, EP/P021859/1, EP/R00501X/1). EHL acknowledges support from the Royal Society and Wolfson Foundation. The authors would like to thank Timothy Moorsom and Oscar Cepedes for their help with Raman microscopy. Data set is online at https://doi.org/10.5518/704.EHL acknowledges support from the Royal Society and Wolfson Foundation. The authors would like to thank Timothy Moorsom and Oscar Cepedes for their help with Raman microscopy. Data set is online at https://doi.org/10.5518/704.
