Elastic Organic Crystals Exhibiting Amplified Spontaneous Emission Waveguides with Standard Red Chromaticity of the Rec.2020 Gamut

Abstract

The use of mechanically flexible molecular crystals as optical transuding media has been demonstrated for a plethora of applications; however, the spectral peaks of optical outputs located mainly in the range of 400−600 nm are insufficient for practical telecommunication and full‐color display applications. Herein, we report two elastically bendable organic crystals that show red emission of the rec.709 gamut under 365 nm UV light irradiation yet generate rec.2020 gamut red optical waveguides and amplified spontaneous emissions when irradiated by a 355 nm laser. Capitalizing on the extended π‐conjugation and donor‐acceptor character, as well as mechanical elasticity, these organic crystals exhibit flexible optical waveguides with Commission Internationale de L'Eclairage (CIE) coordinates of (0.70, 0.29), nearly identical to the red chromaticity of the rec.2020 gamut required for ultrahigh‐definition (UHD) displays. Notably, one of the elastic crystals functioned as a soft resonance cavity, resulting in amplified spontaneous emission waveguides with CIE coordinates of (0.71, 0.29) and the standard red chromaticity of the rec.2020 gamut, both in straight and bent states. This study presents a new avenue for the development of high‐purity red‐emissive crystalline materials to create all‐organic, lightweight, and mechanically compliant optical telecommunication and UHD display devices.This article is protected by copyright. All rights reserved

Crystal Engineering-Driven Sunlight Responsiveness and Flexible Waveguide Transmission

“…In addition to light-driven actuation, organic luminescent molecular crystals hold significant application value in the field of optical waveguides, particularly in the investigation of the optical waveguide properties of flexible crystals. − which is of great significance and potential value in lasers, photonic devices, and optical communication. − Whether in the exploration of light-driven actuation or flexible waveguides, molecular stacking in crystals must adhere to certain principles. For example, photomechanical molecular crystals driven by [2+2] cycloaddition generally require intermolecular double bond distances of ≤4.2 Å .…”