Publications by authors named "Yongyu Cha"

High-efficiency blue phosphorescence and deep-blue laser emissions play a crucial role in organic optoelectronic applications. However, designing metal-free organic blue luminescence with high energy levels of excited states and suppression of nonradiative transitions remains a formidable challenge. Herein, we demonstrate a synthetic strategy for achieving a deep-blue laser and efficient phosphorescence based on confining chromophores in the tetrahedral structure of sp3 hybridization.

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Organic phosphorescence materials provide an opportunity to use triplets for lasing. However, population inversion based on phosphorescence is hard to establish, owing to low luminescent quantum efficiency and intensive optical loss. By comparison, thermally activated delayed fluorescence emitters exhibit excellent optical gain with the aid of the reverse intersystem crossing (RISC) process.

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