Dynamically Tunable Single-layer VO2/metasurface-based broadband THz Cross-Polarization Converter

Numerically, we demonstrate a single-layer THz metadevice, comprised of a 2D array of split ring resonators each with a vanadium oxide (VO2) pad integrated into one of the two capacitive gaps of a unit cell, which exhibits cross-polarization transmission. As the conductivity of VO2 increases, the amplitude of the cross-polarization intensity decreases but maintains a wider broadband range than previously reported for single layered hybrid metamaterial (MM) devices as the VO2 transforms from the insulator to metallic phase. The asymmetric transmission, optically modulated by the device, is higher than that of multi-layered MM devices. Due to the materials properties of VO2, our results introduce a promising method that allows for an active sub-cycle dynamic tenability for THz polarization conversion with multiple modalities using optical, electrical or thermal switching.