Abstract
Circularly polarized (CP) light-emitting diodes (LEDs) hold great potential for next-generation technologies, from efficient photonic to room-temperature quantum devices. Chiral materials enable the generation of CP electroluminescence in LEDs through several different mechanisms, depending on the choice of material and device architecture. Here we summarize the mechanisms that give rise to CP electroluminescence in state-of-the-art materials, including organic small molecules, polymers, inorganic complexes and hybrid halide perovskites. We explore how the device architecture can be used to control the chiroptical properties and device performance, and suggest improvements to maximize the efficiency and dissymmetry factor of future CP LEDs.
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Acknowledgements
This work was supported by European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement number 859752. S.F. acknowledges support from the Rowland Institute at Harvard. This material is based on work supported by the Air Force Office of Scientific Research under award no. FA9550-23-1-0633.
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M.J.F. is an inventor on a patent describing blend polymer systems for CPL applications.
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Furlan, F., Moreno-Naranjo, J.M., Gasparini, N. et al. Chiral materials and mechanisms for circularly polarized light-emitting diodes. Nat. Photon. (2024). https://doi.org/10.1038/s41566-024-01408-z
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DOI: https://doi.org/10.1038/s41566-024-01408-z
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