Xingxu Liu, Langping Tu, Feng Li, Dingxin Huang, Hans Ågren, Guanying Chen. "Unravelling Size-Dependent Upconversion Luminescence in Ytterbium and Erbium Codoped NaYF<sub>4</sub> Nanocrystals." Journal of the American Chemical Society, 2025. doi:10.1021/jacs.4c15683