High-efficient wideband and switchable multifunctional vanadium dioxide-based metasurface

We are happy to announce that Assoc.Prof.Dr. Nguyen Xuan Sang and colleagues recently published their work entitled "High-efficient wideband and switchable multifunctional vanadium dioxide-based metasurface" in the Journal of Physics and Chemistry of Solids.

Abstract:

Integrating switchable and multifunctional capabilities into metasurface structures has become a key area of research, particularly for terahertz (THz) frequencies, which pose significant challenges. In this work, we propose switchable wideband THz metasurfaces with versatile functionalities, including absorption, reflective polarization conversion, and transmissive polarization conversion, utilizing the phase-change material of vanadium dioxide (VO2). Simulations show that the proposed metasurface can dynamically switch from a broadband absorber and reflective cross-polarization conversion to a transmissive cross-polarization converter by controlling the phase of VO2. When VO2 is in its metallic state, the metasurface achieves efficient wideband absorption for backward incident waves in the range of 1.63 to 4.55 THz with absorption exceeding 0.9. It also exhibits reflective polarization conversion for forward linearly polarized waves over a broad frequency range of 1.8–4.65 THz, with a polarization conversion ratio (PCR) greater than 0.9. Switching VO2 to its insulating state enables a broadband transmissive polarization converter for forward y-polarized incidence in the 1.0–5.5 THz range, achieving PCR>0.99 and asymmetric transmission efficiency > 0.45 within a 2.3 THz bandwidth. Wideband performance is maintained over a broad range of incident angles. The proposed switchable metasurface offers potential for advanced smart THz applications with diverse functionalities.