Martin Wood Complex, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU
Professor Ilya Shadrivov, Australian National University
Professor Michael Johnston
Abstract
Efficient polarisation control in the terahertz frequency range is required for many applications, including material characterisation, imaging, and polarimetry. In this presentation, we will provide an overview of our recent developments in metal-based and dielectric gratings that enable polarisation control in the terahertz regime. For metallic gratings acting as linear polarisers, we investigate the effect of wire geometry on the achievable transmission and extinction ratio. We further demonstrate quarter-wave plates based on high-index dielectric gratings and metallic metasurfaces. Finally, we present a translationally invariant metasurface capable of generating circularly polarised vortex beams.