Open AccessEnergy Transfer between Tb 3+ and Eu 3+ in LaPO 4 : Pulsed versus Switched‐off Continuous Wave Excitation
Author(s) -
Luo Yuxia,
Liu Zhenyu,
Wong Hon Tung,
Zhou Lei,
Wong KaLeung,
Shiu Kwok Keung,
Tanner Peter A.
Publication year - 2019
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.201900487
Subject(s) - excitation , luminescence , ion , doping , materials science , energy transfer , atomic physics , quenching (fluorescence) , laser , analytical chemistry (journal) , continuous wave , diode , optoelectronics , fluorescence , chemistry , optics , physics , organic chemistry , quantum mechanics , chromatography
The energy transfer (ET) between Tb 3+ and Eu 3+ is investigated experimentally and with available theoretical models in the regime of high Tb 3+ concentrations in ≈30 nm LaPO 4 nanoparticles at room temperature. The ET efficiency approaches 100% even for lightly Eu 3+ ‐doped materials. The major conclusion from the use of pulsed laser excitation and switched‐off continuous wave laser diode excitation is that the energy migration between Tb 3+ ions, situated on La 3+ sites with ≈4 Å separation, is not fast. The quenching of Tb 3+ emission in singly doped LaPO 4 only reduces the luminescence lifetime by ≈50% in heavily doped samples. Various theoretical models are applied to simulate the luminescence decays of Tb 3+ and Tb 3+ , Eu 3+ ‐doped LaPO 4 samples of various concentrations and the transfer mechanism is identified as forced electric dipole at each ion.