Layered full-color tunable structural colors utilizing Ge2Sb2Se4Te1 chalcogenide phase change material

Ge 2 Sb 2 Se 4 Te 1 , a newly developed phase change material derived from Ge 2 Sb 2 Te 5 , has garnered significant interest among researchers due to its numerous advantages.Here, its phase change characteristics under the electron beam evaporation method are thoroughly investigated, and a layered tunable color structure is proposed.Based on the low intrinsic absorption of Ge 2 Sb 2 Se 4 Te 1 material, it exhibits excellent dynamic tunability along with vivid color appearance including high brightness and high purity.In experiments, five representative colors-red, green, blue, yellow, and purple-were successfully prepared.The peak reflection of these samples averaged 92%, and when heated to 320C, the temperature at which the phase transition of Ge 2 Sb 2 Se 4 Te 1 occurred, reflection loss was barely observed.In addition, after phase transition, the sideband reflection at non-target wavelengths decreased by 30%, bringing high-purity crystalline-state colors and noticeable color changes.Therefore, it is believed that the structural color scheme proposed here will contribute to the development of many fields including smart glasses, artificial retinal devices, high-resolution displays, and beyond.