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Updated: Oct 20, 2025
Synthesis of Core-shell Lanthanide-doped Upconversion Nanocrystals for Cellular Applications
Published on: November 10, 2017
Lanthanide Upconverted Microlasing: Microlasing Spanning Full Visible Spectrum to Near-Infrared under Low Power, CW
Xiang-Fei Yang1, Ze-Yu Lyu1, Hao Dong1
1Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, PKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
Abstract:
The miniaturization of lasers holds promise in ultradense data storage and biosensing, but greater pump power is required to reach the lasing thresholds to overcome increased optical losses with reduced resonant cavity sizes. Here, the whispering galley mode (WGM) of Yb3+ /Tm3+ doped upconversion nanoparticles (UCNPs) coupled with microcavities (≈5 µm) is used to achieve ultralow threshold upconverted lasing at 800 nm with excitation fluences as low as 4 W cm-2 . The continuous-wave (CW) upconverted lasing, with a Q factor on the order of 103 , can remain stable for more than 6 h. In addition, ultralow threshold upconverted microlasers spanning the full visible spectrum from Yb3+ /Er3+ , Yb3+ /Ho3+ , and Yb3+ /Tm3+ doped UCNPs are obtained with the same WGM cavity design. These upconverted microlasers working under low power CW 980 nm laser will enable promising applications in biosensing and imaging.
