Robust Shape-Memory Chiral Photonic Elastomers With Multi-Stimuli Responsiveness.

Stimuli-responsive materials are pivotal for advanced photonics, yet achieving ones with multiple-dimensional manipulation and high robustness remains a challenge. Here, we present a shape-memory chiral photonic platform with multi-stimuli-responsiveness by sophisticatedly controlling the crosslinking chemistry and density of a triplet-triplet annihilation upconversion featured cholesteric elastomer. A thermally resettable shape memory effect on structural colors is induced by force in the elastomer with an oligomer-lowered crosslinking density, which also exhibits exceptional stretchability and enhanced optics, a remarkable 259 nm blueshift over 215% strain. The covalent incorporation of annihilators secures homogeneity and stability of the system. The material possesses programmable optical properties, including chirally, thermally, and mechanically regulated structural colors and photoactivated luminescence, enabling high-dimensional information encryption with accessibility to scalable spray-printing. This work provides a versatile material strategy for cutting-edge optical encryption and paves the way for next-generation wearable sensors, adaptive optical devices, and interactive camouflage technologies.