Programmable polarization and structural color in a stretchable luminescent chiral liquid crystal elastomer

Abstract

Flexible luminescent materials, especially those exhibiting circularly polarized luminescence (CPL), have attracted increasing attention in wearable electronics, optical sensing, and information encryption owing to their adaptable responsiveness and on-demand tunable emission. However, the simultaneous achievement of high luminescence dissymmetry factor and efficiency in flexible materials remains a fundamental challenge, as it requires balancing chiral assembly against self-quenching. Herein, we construct a chiral liquid crystal elastomer film that integrates chirality, fluorescence, and elastomeric responsiveness into a single multifunctional material. Specifically, this tunable one-dimensional photonic crystal exhibits three critical improvements: (i) substantial enhancement of photoluminescence quantum yield through homogeneous fluorophore distribution within the elastomeric matrix, (ii) significant improvement of circularly polarized light emission achieved by precise bandgap-fluorescence spectral matching, which achieves high luminescence dissymmetry factor, and (iii) reversible polarization modulation realized via strain-responsive bandgap with excellent fatigue-resistant. The combination of broad multicolor tunability CPL and robust fatigue-resistant deformation enables the successful fabrication of a triplex flexible photonic encryption prototype through strain engineering. This study broadens the applicability of chiral photonic materials in flexible optoelectronics and establishes a generalizable strategy for engineering adaptive photonic films.