Tunable SiO2-VO2 metasurfaces for multidimensional structural color control in optical applications

This study introduces a multidimensional structural color tuning method for a dual-layer rectangular prism structure composed of SiO₂-VO₂ and based on flexible materials. Using the phase transition characteristics of VO₂, specifically the meta-insulator phase transition and benefiting from the stretchability, high-temperature resilience, and low-temperature resistance of PDMS material, the metasurface structures exhibit stability in optical performance across a range of challenging temperature and deformation conditions, this study achieves flexible adjustment of structural color and modulation of solar spectrum reflectance by optimizing geometric parameters and controlling temperature. The results demonstrate substantial color changes in the structural color, shifting from the blue range to the green range when altering the period P from 280nm to 380nm, and exhibiting distinct color variations when transitioning VO₂ from insulating state to a metallic state upon temperature variation. The stimulation results demonstrate that the manipulation of key parameters such as side length W₁, side width W₂, and period P yields discernible alterations in both the structural color and reflection spectrum of the SiO₂-VO₂ structure. This work is simulated using Finite-Difference Time-Domain (FDTD) software. Therefore, the multidimensional structural color tuning method proposed in this study for the SiO₂-VO₂ dual-layer rectangular prism structure based on flexible materials showcases significant application potential in various fields such as smart color-changing materials, energy management, and information displays, enabling flexible control of structural color and switching of solar spectrum reflectance.