Polarization Conversion and Absorption of Multifunctional All-dielectric Metamaterial Based on Vanadium Dioxide

In this paper, we propose a kind of multi-functional all-dielectric metamaterial (ADMM), which is composed of vanadium dioxide (VO2), silicon, and silicon dioxide. Two functions of polarization conversion and wave absorption are realized by using the phase change characteristics of VO2. When the VO2 is in the insulating state, the structure has the function of transmission polarization conversion and realizes the conversion from line-polarized wave to cross-polarized wave. The polarization conversion rate (PCR) is more than 95% in 250-nm bandwidth. The reason of the high PCR is analyzed from the perspective of the amplitude and phase of the field component. The first-order Mie resonance is found by looking at the distribution of electric field. When the VO2 is in the metallic state, the structure has the absorption function. Within the bandwidth of 482 nm, the absorption efficiency is more than 80%. By looking at the distribution of electric field and magnetic field, the main reason for the strong absorption effect is explained. Finally, the effect of VO2 conductivity on performance was studied.