Multistate structural colors enabled by dual chalcogenide phase-change materials Ge₂Sb₂Se₄Te₁/Sb₂S₃

Phase-change-material-based structural colors provide a promising route toward dynamically tunable optical devices. However, achieving high brightness, low angular sensitivity, and multistate color modulation simultaneously remains challenging. Here, we propose and experimentally demonstrate a six-layer asymmetric Fabry-Pérot cavity combining two chalcogenide phase-change materials, Sb₂S₃ and Ge₂Sb₂Se₄Te₁, to achieve high-brightness red, orange, and yellow structural colors. The experimental results are in good agreement with theoretical simulations. All fabricated samples exhibit reflectance exceeding 80% in the visible light spectrum and maintain excellent color stability over incident angles from 0° to 60°. By exploiting the distinct crystallization temperatures of Sb₂S₃ and Ge₂Sb₂Se₄Te₁, step-wise phase transitions shift the colors from the initial red, orange, and yellow to dark states and subsequently to low-saturation gray tones. Consequently, the three primary colors are expanded into a dynamic matrix of nine distinct colors, achieving multistate color manipulation based on a dual-phase-change mechanism.