The Er^3＋/Yb^3＋ co-doped TeO2-Nb2O5-Li2O glass is prepared by conventional melting method, and its upconversion spectra are measured. The intense green upconversion luminescence upon excitation with a 976 nm laser d...The Er^3＋/Yb^3＋ co-doped TeO2-Nb2O5-Li2O glass is prepared by conventional melting method, and its upconversion spectra are measured. The intense green upconversion luminescence upon excitation with a 976 nm laser diode is observed with the naked eyes. The dependence of luminescence intensity on the ratio of Yb^3＋/Er^3＋ is discussed in detail, and the relationship between the ratio of green luminescence intensity to red luminescence intensity and the ratio of Yb^3＋/Er^3＋ is also studied, The luminescence intensity increases with the ratio of Yb^3＋/Er^3＋ increasing. The ratio of Yb^3＋/Er^3＋ plays a more important role than the concentration of Er^3＋ in determining the upconversion luminescence intensity. The ratio of green luminescence intensity to red luminescence intensity reaches a maximum when ratio of Yb^3＋/Er^3＋ is 3. Thus the glass could be one of the potential candidates for LD pumping solid-state lasers.展开更多
Transparent glass ceramics were prepared from the phosphosilicate system by melt-quenching devitrification（MQD） method, i.e., nanocrystals spontaneously form during cooling of the melts. Introduction of 2.5 wt.% Yb2...Transparent glass ceramics were prepared from the phosphosilicate system by melt-quenching devitrification（MQD） method, i.e., nanocrystals spontaneously form during cooling of the melts. Introduction of 2.5 wt.% Yb2O3 and 0.5 wt.% Er2O3 into the glass melt induced the change of type and concentration of crystals. The comparison of rheological and thermodynamic properties of both undoped and Yb^3＋/Er^3＋ doped melts showed that addition of Yb^3＋/Er^3＋ oxides caused increase of liquid fragility, and degree of medium-range order. In addition, the thermodynamic barriers for nucleation ΔG＊ as a function of reduced temperature T/Tm were calculated with an assumption of wetting angle θ=90o, Yb^3＋/Er^3＋ doped melt tended to firstly nucleate as compared to undoped melt at small undercooling.展开更多
基金Project supported by the National Natural Science Foundation of China （Grant No 60307004） and the Science and Technology Program of Guangzhou, Guangdong province, China （Grant No 2004Z2-D0131）.
文摘The Er^3＋/Yb^3＋ co-doped TeO2-Nb2O5-Li2O glass is prepared by conventional melting method, and its upconversion spectra are measured. The intense green upconversion luminescence upon excitation with a 976 nm laser diode is observed with the naked eyes. The dependence of luminescence intensity on the ratio of Yb^3＋/Er^3＋ is discussed in detail, and the relationship between the ratio of green luminescence intensity to red luminescence intensity and the ratio of Yb^3＋/Er^3＋ is also studied, The luminescence intensity increases with the ratio of Yb^3＋/Er^3＋ increasing. The ratio of Yb^3＋/Er^3＋ plays a more important role than the concentration of Er^3＋ in determining the upconversion luminescence intensity. The ratio of green luminescence intensity to red luminescence intensity reaches a maximum when ratio of Yb^3＋/Er^3＋ is 3. Thus the glass could be one of the potential candidates for LD pumping solid-state lasers.
基金Project supported by the Natural Science Fund of Elite Young Researchers of Shandong Province(2008BS04004)
文摘Transparent glass ceramics were prepared from the phosphosilicate system by melt-quenching devitrification（MQD） method, i.e., nanocrystals spontaneously form during cooling of the melts. Introduction of 2.5 wt.% Yb2O3 and 0.5 wt.% Er2O3 into the glass melt induced the change of type and concentration of crystals. The comparison of rheological and thermodynamic properties of both undoped and Yb^3＋/Er^3＋ doped melts showed that addition of Yb^3＋/Er^3＋ oxides caused increase of liquid fragility, and degree of medium-range order. In addition, the thermodynamic barriers for nucleation ΔG＊ as a function of reduced temperature T/Tm were calculated with an assumption of wetting angle θ=90o, Yb^3＋/Er^3＋ doped melt tended to firstly nucleate as compared to undoped melt at small undercooling.
