Thermally Responsive White Circularly Polarized Light from Elastic Chiral Crystals via Dual Fluorescence‐Phosphorescence

Single‐component chiral crystals are presented exhibiting intrinsic white circularly polarized luminescence (WCPL) through simultaneously integrating blue fluorescence (455 nm) and yellow phosphorescence (555 nm), achieving ideal white‐light emission with Commission Internationale de l'Éclairage (CIE) coordinates of (0.32, 0.33) and a photoluminescence quantum yield of 22%. The WCPL properties are thermally responsive, enabling dynamic light tuning between cool (CIE: 0.29, 0.25) and warm (CIE: 0.39, 0.48) white by modulating the fluorescence/phosphorescence ratio. Remarkably, these crystals exhibit mechanical flexibility, allowing their integration into bendable optical systems. The efficient room‐temperature phosphorescence stems from bromine‐enhanced spin‐orbit coupling, while the elastic crystal lattice facilitates robust mechanical performance. By leveraging these attributes, flexible white‐light waveguides (CIE: 0.31, 0.33) with spatiotemporal transmission control are demonstrated. This work provides a crucial reference for single‐component WCPL‐active crystals with combining stimuli‐responsiveness and mechanical adaptability, offering exciting prospects for flexible chiroptical devices and dynamic anti‐counterfeiting systems.