Dynamic Switching of the Circularly Polarized Luminescence of Disubstituted Polyacetylene by Selective Transmission through a Thermotropic Chiral Nematic Liquid Crystal

Abstract

The circularly polarized luminescence (CPL) of chiral disubstituted liquid‐crystalline polyacetylene (di‐LCPA) can be dynamically switched and amplified from left‐ to right‐handed CPL and vice versa through the selective transmission of CPL across a thermotropic chiral nematic liquid crystal (N*‐LC) phase. By combining a chiral di‐LCPA CPL‐emitting film with an N*‐LC cell and tuning the selective reflection band of the N*‐LC phase to coincide with the CPL emission band, a CPL‐switchable cell was constructed. The phase change induced by the thermotropic N*‐LC cell by varying the temperature leads to a change in the selective transmission of CPL, which enables the dynamic switching and amplification of CPL. It is anticipated that CPL‐switchable devices might find applications in switchable low‐threshold lasers and optical memory devices.

Ultrastrong Red Circularly Polarized Luminescence Promoted from Chiral Transfer and Intermolecular Förster Resonance Energy Transfer in Ternary Chiral Emissive Nematic Liquid Crystals

“…As shown in the POM graphics of wedge cells of Supporting Information Figure S12, the planar Grandjean–Cano lines method was executed to measure the helical pitches (P) of B-N*-LCs and T-N*-LCs at 25 °C, and summary data are listed in Table . In the past several years, some reports have proved that chiral binaphthyl derivative dopants could show stronger helical twisting (HTP) power ability by introducing the more rigid aromatic substituents on the 2,2′-positions of the binaphthyl rings. − Akagi’s group demonstrated that the hexamethylene alkane [−(CH 2 ) 6 −] spacer of binaphthyl derivative could exhibit the stronger twisting power compared with the dodecamethylene [−(CH 2 ) 12 −] structure because the long alkane chain could make the segment at the 2,2′-position of the binaphthyl rings more flexible . In this work, we also found the helical pitches (P) of both B-N*-LCs and T-N*-LCs incipiently decreased and later increased with the length change of the alkane chains of the chiral dopants Guest A (Table ).…”

Circularly Polarized Photodetectors Based on Chiral Materials: A Review

“…Cholesteric liquid crystals (CLCs) are ordered liquid crystal structures that exhibit intrinsic periodicity in the form of helical supramolecular structures. They have attracted special attention as optical diffraction gratings for light-emitting diodes, reflection-free lasers, tunable color filters, and reflective devices ( San Jose et al, 2014 ; Ryabchun and Bobrovsky, 2018 ). Cholesteric structures provide an effective strategy to improve the performance of CPL photodetectors because of their various advantages.…”

Chiroptical property tuning of supramolecular assemblies in polymer matrices

“…These chiroptical materials have been developed using lanthanide complexes, small organic molecules, π‐conjugated polymers, and supramolecular assemblies . Supramolecular assemblies are particularly attractive tools because their chiroptical properties are generated through intermolecular interactions that can be tuned by external stimuli, such as temperature, light, pH, electric field, magnetic field, and additives . There are many interesting reports on the chiroptical properties of supramolecular assemblies in solution.…”