Spectroscopic study of the energy transfer effect in Pr～(3+)/Tm～(3+) codoped LaF_3 nanocrystal system

LaF3 nanocrystals codoped with Pr3+ and Tm3+ ions were synthesized at lower temperatures with hydrothermal method. The characterization results of XRD, ATM and STEM suggests that the structure of the nanocrystal is hexagonal, and its size is about 30 nm. Using 355 nm laser to pump the codoped nanocaystal samples, we successfully observed the fluorescence emission originating from the energy transfer of Tm3+ to Pr3+. The luminescence properties and the mechanism of the energy transfer are investigated with laser spectroscopy.