Symmetric Ge₂Sb₂Te₅ based metamaterial absorber induced dynamic wide-gamut structural color

Plasmonic color has played a critical role for its applications in color printing and display owing to the advantages of high-resolution and durability. Recently, increasing attempts have been performed to actualize dynamic structural color. Here theoretically proposed is the generation of wide color gamut in symmetric Ge₂Sb₂Te₅ (GST) based metamaterial absorber. By introducing a periodic metallic nanodisk array on top of the composite structure, the color variation arises from GST transition between amorphous phase and crystalline phase can be enhanced significantly. Due to the interplay of the localized/propagating surface plasmons, Fabry–Perot cavity mode and Wood's anomaly with different resonant frequencies, both hue and saturation of the structural color can be tuned accordingly through adjusting the structural geometry of the nanodisks. It is demonstrated that up to 74% and 94% of the sRGB and CMY(K) space can be obtained with this phase-change metamaterial display. This finding paves the way toward the development of practical platform for color printing and display applications. (paper)