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arXiv · 2108.08954

Broadband switchable terahertz half-/quarter-wave plate based on a graphene-metal hybrid metasurface

Xiaoqing Luo·Juan Luo·Fangrong Hu·Guangyuan Li
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Abstract

Metasurfaces incorporating graphene hold great promise for dynamic manipulation of terahertz waves. However, it remains challenging to design a broadband graphene-based terahertz metasurface with switchable functionality of half-wave plate (HWP) and quarter-wave plate (QWP). Here, we propose a graphene-metal hybrid metasurface for achieving broadband switchable HWP/QWP in the terahertz regime. Simulation results show that, by varying the Fermi energy of graphene from 0 eV to 1 eV, the function of the reflective metasurface can be switched from an HWP with polarization conversion ratio exceeding 97% over a wide band ranging from 0.7 THz to 1.3 THz, to a QWP with ellipticity above 0.92 over 0.78-1.33 THz. The sharing bandwidth reaches up to 0.52 THz and the relative bandwidth is as high as 50%. We expect this broadband and dynamically switchable terahertz HWP/QWP will find applications in terahertz sensing, imaging, and telecommunications.

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Xiaoqing Luo, Juan Luo, Fangrong Hu, Guangyuan Li. 2021-08-20. Broadband switchable terahertz half-/quarter-wave plate based on a graphene-metal hybrid metasurface. https://doi.org/10.1088/1674-1056%2Fac80a8

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