Influence of Crystal Structure on the Fluorescence Emission of Eu3+:LaOF Nanocrystals

Optical transitions of Eu3+-doped LaOF nanocrystals with tetragonal and rhombohedral structures were studied experimentally using laser spectroscopic method. Fluorescence emissions from D-5(1) and D-5(0) of Eu3+ in LaOF nanocrystals were detected by exciting the sample with a 532 nm pulsed laser, and the influence of local symmetry on the fluorescence emission of doped ions was observed. The specific crystalline phase as well as the local symmetry on the fluorescence emission was investigated in both the frequency domain and time domain. It was found that Eu3+ ions doped in the tetragonal crystal structure present more efficient fluorescence emission, which was explained by lower symmetric distribution of local field at the doped ions.