Optical Gain at 637 nm Wavelength in Polymer Waveguide Amplifier Under Commercial LED Pumping for Planar Photonic Integration (Advanced Optical Materials 13/2022)

This cover image shows optical amplification at 637 nm that is achieved in polymer waveguides doped with thermally activated delayed fluorescence (TADF) molecules. Under excitation of low-cost light-emitting diodes, the molecules realize the process of converting blue-violet light into red light, which depends on the continuous absorption band of the material and reverse intersystem crossing process. The results, presented by Dan Zhang, Guohua Xie, and co-workers in article number 2200205, open new avenues for the application of TADF materials in photonic integrated chips.