The upconversion (UC) luminescence and color tunable properties of Tb3+ ions were investigated by steady spectral under 980 LD excitation in the Ca0.15Zr0.85O1.85:Yb,Tb inverse opals fabricated by the self-assembly technique in combination with a sol-gel method. The in-hibition of UC emission was inspected if the Tb3+ UC emission band was in the regions of the photonic bandgap, while enhancement of the UC emission occurred if the UC emission band located at the edge of the bandgap. Color modification of the UC emission was successfully ob-tained by the suppression or enhancement effect of the photonic band gap on the UC emission.
Upconversion(UC) luminescence photonic band gap materials Tb-Yb co-doped phosphate inverse opal photonic cryst...
Kan Zhu~(1,a),Zhengwen Yang~(1,b),Dong Yan~1,Zhiguo Song~1,Dacheng Zhou ~1,Rongfei Wang~1, and Jianbei Qiu~(1,c) 1 Key Lab of Advanced Materials in Rare & Precious and Non-ferrous Metals,Ministry of Education,Key Laboratory of Advanced Materials of Yunnan Province,College of materials science and engineering,Kunming University of Science and Technology,Xuefu RD,Kunming,650093,China
Three-dimensional-ordered Yb/Er co-doped Bi2Ti2O7 inverse opal, powder, and disordered reference samples are prepared and their upconversion (UC) emission properties and mechanisms are investigated. Significant suppression of UC emission is detected when the photonic band-gaps overlap with Er3+ UC green emission bands. Interestingly, green and red UC emissions follow a two-photon process in the powder sample but a three-photon one in the inverse opal.
The up-conversion of Er3+/Yb3+co-doped transparent glass-ceramics 50SiO2-10AlF3-5TiO2-30BaF2-4LaF3-0.5ErF3-0.5YbF3 containing Ba2 LaF7 nanocrystals under the changing of heat treatment temperature and time were investigated.The Ba2 LaF7 nanocrystals precipitated from the glass matrix was confirmed by X-ray diffraction(XRD).The structural investigation carried out by XRD and transmission electron microscopy(TEM) evidenced the formation of cubic Ba2 LaF7 nanocrystals with crystal size of about 14 nm.Comparing with the samples before heat treatment,the high efficiency up-conversion emission of Er3+/Yb3+co-doped samples was observed in the glass-ceramics under 980 nm laser diode excitation.The increase in red emission intensity bands was stronger than the green bands when the crystal size increased.The mechanism for the up-conversion process in the glass-ceramics and the reasons for the increase of Er3+/Yb3+co-doped up-conversion intensity after heat treatment were discussed.
