Ultrastrong Circularly Polarized Luminescence Triggered by the Synergistic Effect of Chiral Coassembly and Selective Reflective Cholesteric Liquid Crystal Film

Enhancing the dissymmetry factor (glum) is crucial for circularly polarized luminescence (CPL) applications. Herein, we present an innovative strategy achieving an ultrastrong |glum| of 1.73. This is accomplished through the synergistic effect of coassembly of the CPL-emitting ternary liquid crystal (T-N*-LC, |glum| = 0.47) and the selective reflection (λ = 590 nm) of the polymer cholesteric liquid crystal (CLC) within a composite system. Unlike the mismatched chirality combination (|glum| = 1.42, ΔFL = 57%), the matched combination demonstrates an ultrastrong CPL signal with a |glum| of 1.73 and a low ΔFL of 50% when the CPL direction of the T-N*-LC agrees with the CLC film's chirality. Furthermore, we alter the matching degree of the composite system by applying a direct-current (DC) electric field to realize the CPL switch. This study paves the way for developing outstanding CPL-active display materials through synergistic amplification of glum.