Eu^(3+) ion doped cubic Na_5Lu_9F_(32) single crystals with high quality were synthesized by a modified Bridgman method by using a high 70-90 ℃/cm temperature gradient for cross solid-liquid interface. The optical sp...Eu^(3+) ion doped cubic Na_5Lu_9F_(32) single crystals with high quality were synthesized by a modified Bridgman method by using a high 70-90 ℃/cm temperature gradient for cross solid-liquid interface. The optical spectroscopic investigations of the obtained single crystal were reported for the absorption, excitation and emission. The experimental results show that a strong red emission at 609 nm attributing to the ~5D_0→~7F_2 transition of Eu^(3+) doped Na_5Lu_9F_(32) single crystals can be obtained under the excitation of 394 nm light and reach the maximum when the Eu^(3+) doping concentration is 4 mol% in present research. The local covalent is enhanced and symmetry is reduced with the increase of Eu^(3+) concentrations inferring from the strength parameters Ω_2 and Ω_4 calculated by their measured emission spectra. The CIE chromaticity coordinates of the 4 mol% Eu^(3+) doped Na_5Lu_9F_(32) single crystals are calculated as(x=0.626, y=0.3736), which are close to the NTSC standard values for red(x=0.67, y=0.33). The experimental results reveal that the single crystal can be used as potential red phosphors under near ultraviolet(NUV) light excitation.展开更多
基金Funded by the National Natural Science Foundation of China(Nos.51772159 and 51472125)the Natural Science Foundation of Zhejiang Province(No.LZ17E020001)KC Wong Magna Fund in Ningbo University
文摘Eu^(3+) ion doped cubic Na_5Lu_9F_(32) single crystals with high quality were synthesized by a modified Bridgman method by using a high 70-90 ℃/cm temperature gradient for cross solid-liquid interface. The optical spectroscopic investigations of the obtained single crystal were reported for the absorption, excitation and emission. The experimental results show that a strong red emission at 609 nm attributing to the ~5D_0→~7F_2 transition of Eu^(3+) doped Na_5Lu_9F_(32) single crystals can be obtained under the excitation of 394 nm light and reach the maximum when the Eu^(3+) doping concentration is 4 mol% in present research. The local covalent is enhanced and symmetry is reduced with the increase of Eu^(3+) concentrations inferring from the strength parameters Ω_2 and Ω_4 calculated by their measured emission spectra. The CIE chromaticity coordinates of the 4 mol% Eu^(3+) doped Na_5Lu_9F_(32) single crystals are calculated as(x=0.626, y=0.3736), which are close to the NTSC standard values for red(x=0.67, y=0.33). The experimental results reveal that the single crystal can be used as potential red phosphors under near ultraviolet(NUV) light excitation.
