Realization of Reflective Color Generation and Controllable absorption in Near-Infrared Based on Active Nanocrystal Metamaterials Absorber

Abstract

The conventional color was realized by dye or organic paints. But these colors be vulnerable to Ultra-Violet light, discoloration occurs over time. To solve this problem, the structural color was proposed. To implement the structural color, An absorber is needed that can reflect a selective wavelength. The representative optical absorber is used Fabry-Perot structure. Conventional absorber has fixed optical properties after fabricated. To make up for these limitations, researchers used to Nanocrystal to tune material properties [1] or, an intuitive approach using phase change material (PCM) [2,3]. In the case of nanocrystals, the optical properties of the material can be changed, only in before fabrication, and the bulk PCM has a disadvantageous that is difficult to apply due to its large optical loss. In this study, we demonstrated a flexible reflective color filter with changeable Near-Infrared (NIR) absorption based on the solution-processable that without annealing process Vanadium dioxide (VO2) nanocrystal absorber. In this case, the optical loss can be controlled by only the nanocrystal size, and thickness without lost a phase change property. Based on these advantages, the main additive colors with NIR controllable absorption has been demonstrated. Furthermore, we exploit advanced VO2 that W-doped in which phase change temperature can be drastically reduced, it can be expected for anti-counterfeiting technology and display industry.