Bi-functional polarization conversion in hybrid graphene-dielectric metasurfaces

• DOI: 10.1364/ol.44.005683
• Publication Date: 2019-11-20T15:12:19Z
• Authors: Shengnan Guan; Jierong Cheng; Tiehong Chen; Shengjiang Chang
• Keywords: Biasing

In this Letter, we propose a hybrid graphene-dielectric metasurface as bi-functional polarization converter. It can switch between reflective half-wave plate and quarter-wave around 1 THz by merely applying external biasing voltage, without reoptimizing the dielectric structure. Switching of two wave plates originates from distinct dispersion orthogonal eigenmodes with chemical potential, which is further explained overlapping graphene resonance modes. Compared graphene-metallic metasurfaces, combination microstructures offers an alternative solution for active terahertz devices high efficiency large flexibility.