High‐Purity Hybrid Structural Colors by Enhancing Optical Absorption of Organic Dyes in Resonant Cavity

Abstract

This work presents a novel approach of incorporating an ultrathin dye film into a classic dielectric‐absorber‐dielectric‐metal resonator configuration for generating high‐purity reflective structural colors. Utilizing a thin film of organic dye having the same color as the targeted reflection color as a part of the cavity layer in the structure, its absorption at complementary color wavelengths is significantly enhanced due to the strong cavity resonances, hence reflection at the unwanted wavelengths strongly suppressed, leading to the improved purity of the desired reflective color. This design principle can be applied to create essentially all colors, and is demonstrated by experiment to produce high‐purity blue and red colors. In addition, the fabricated device exhibits outstanding stability under UV exposure without additional protections compared to traditional organic pigments. The proposed method in this work largely simplifies the design process of high‐purity structural colors, which paves the way for more potential applications in various fields.A simple approach that incorporates an ultrathin dye film into a classic dielectric‐absorber‐dielectric‐metal multilayered structure is presented to produce high‐purity reflective colors. The enhanced optical absorptions of the colored dye layer as a result of the strong cavity resonances can effectively suppress the reflection within the unwanted wavelength range, thus significantly improving the purity of the desired reflective colors.