Pushing the Limits: Down‐Converting Er3+‐Doped BaF2 Single Crystals with Photoluminescence Quantum Yield Surpassing 100%. Adv. Optical Mater. 2024, 2303094

E.I. Madirov, S.V. Kuznetsov, V.A. Konyushkin, D. Busko, B. S. Richards, A. Turshatov, Pushing the Limits: DownConverting Er3+Doped BaF2 Single Crystals with Photoluminescence Quantum Yield Surpassing 100%. AdvOptical Mater. 2024, 2303094. https://doi.org/ 10.1002/adom.202303094