Crystals of LiKGdF 5∶Er 3+, Tb 3+ grown by the hydrothermal synthesis technique with concentrations of 2% and 0.4% were analysed. By using site selective excitation measured at low temperature, luminescence and ex...Crystals of LiKGdF 5∶Er 3+, Tb 3+ grown by the hydrothermal synthesis technique with concentrations of 2% and 0.4% were analysed. By using site selective excitation measured at low temperature, luminescence and excitation spectra from Er 3+ and Tb 3+ ions embedded in LiKGdF 5 were clearly separated. The lifetimes of the emitting levels 4S 3/2 of Er 3+ and 5D 4 of Tb 3+ were also determined. Following the site selective spectroscopy study, the dominant energy transfer process from Tb 3+ to Er 3+ in the crystal was then investigated via transient experiments.展开更多
The upconversion fluorescence of Er^3＋ ions in LiKGdF5 ： Er^3＋, Dy^3＋ single crystal was studied under 785, 514.5, and 980 nm laser excitation. With the laser excitation set at 785 nm, strong green （centered at 5...The upconversion fluorescence of Er^3＋ ions in LiKGdF5 ： Er^3＋, Dy^3＋ single crystal was studied under 785, 514.5, and 980 nm laser excitation. With the laser excitation set at 785 nm, strong green （centered at 543 nm） upconversion emissions, as well as weak red （651 nm）, violet （406 nm）, and blue （470 nm） upconversion emissions were obtained. With 514.5 nm laser excitation, violet （406 nm） and blue （470 nm） upconversion emissions were observed. Under 980 nm laser excitation, strong green （543 nm） and weak red （651） emissions were also obtained. The laser power dependence of the upconverted emissions was investigated to understand the upconversion mechanism. The excited state absorption （ESA） and the energy transfer （ET） processes were discussed as the possible mechanisms for all upconversion emissions.展开更多
文摘Crystals of LiKGdF 5∶Er 3+, Tb 3+ grown by the hydrothermal synthesis technique with concentrations of 2% and 0.4% were analysed. By using site selective excitation measured at low temperature, luminescence and excitation spectra from Er 3+ and Tb 3+ ions embedded in LiKGdF 5 were clearly separated. The lifetimes of the emitting levels 4S 3/2 of Er 3+ and 5D 4 of Tb 3+ were also determined. Following the site selective spectroscopy study, the dominant energy transfer process from Tb 3+ to Er 3+ in the crystal was then investigated via transient experiments.
基金Project supported by a grant from Department of Education of Zhejiang Province (20060496)
文摘The upconversion fluorescence of Er^3＋ ions in LiKGdF5 ： Er^3＋, Dy^3＋ single crystal was studied under 785, 514.5, and 980 nm laser excitation. With the laser excitation set at 785 nm, strong green （centered at 543 nm） upconversion emissions, as well as weak red （651 nm）, violet （406 nm）, and blue （470 nm） upconversion emissions were obtained. With 514.5 nm laser excitation, violet （406 nm） and blue （470 nm） upconversion emissions were observed. Under 980 nm laser excitation, strong green （543 nm） and weak red （651） emissions were also obtained. The laser power dependence of the upconverted emissions was investigated to understand the upconversion mechanism. The excited state absorption （ESA） and the energy transfer （ET） processes were discussed as the possible mechanisms for all upconversion emissions.
