A dynamically switchable metamaterial device with multiple functions based on vanadium dioxide

Based on the phase transition properties of vanadium dioxide (VO₂), a metamaterial device is designed in this paper, which can achieve multiple switchable functions. When VO₂ is in the metallic state, the proposed device can realize broadband absorption with peak absorbance more than 90 % in the frequency range of 2.40–6.73 THz and broadband linear polarization conversion (LPC) with polarization conversion ratio (PCR) greater than 90% in the range of 1.80–4.21 THz, respectively, depending on whether the incidence of terahertz (THz) electromagnetic (EM) wave is from top side or bottom side. When VO₂ is in the insulated state, the proposed device can achieve LPC of half-reflection and half-transmission (HRHT) and transmissive linear-to-circular (LTC) polarization conversion. The study in this paper has guiding significance in the design of THz metamaterial devices with multiple functions.