镱离子敏化与温度对铒离子掺杂碲酸盐玻璃上转换光谱的影响

Effects of Temperature and Ytterbium Sensitizing on Upconversion Characteristics in Erbium-doped Tellurite Glasses

用熔融-淬冷法制备了玻璃样品系列75TEO_2-20ZnO-(4.6-x)La_2O_3-0.4Er_2O_3-xYb_2O_3(x=0,0.4,0.8,2.0,3.2,4.0),研究了镱离子的掺入及温度的变化对该玻璃系统上转化光谱的影响,结果表明:在常温下,当Yb^(3+)离子浓度达到2mol%时,上转换红光和545nm绿光都达到了最大值,此时545nm绿光强度是未掺Yb^(3+)时的6倍左右,红光强度为未掺Yb^(3+)时的4倍左右;当温度在8～300K变化时,530nm绿光强度随着温度的升高而增大,545nm绿光与657nm红光强度随着温度的升高首先增大,在80K达到最大值,然后随着温度的升高而下降.通过速率方程,分析了镱离子的敏化及温度对该玻璃系统上转换光谱的影响.

Tellurite glasses 75TeO2-20ZnO-（4.6-x）La2O3- 0.4Er2O3-xYb2O3 （x=0, 0.4, 0.8, 2.0, 3.2, 4.0） were prepared by conventional melt-quenching method. The effects of temperature （8 300K） and the ytterbium concentration on upconversion characteristics were investigated. When the Yb^3＋ concentration is 2mol%, the upconversion emission intensities around 545nm and 657nm present 6-fold and 4-fold enhancement, respectively, compared with Er^3＋-doped glass at room temperature. The green emission intensities around 530nm present monotonic increase with increasing temperature from 8K to 300K. The green emission intensities around 545nm increase with increasing temperature from 8K to 80K and reach the maximum at around 80K, then decrease with increasing temperature from 80K to 300K. The characteristics of the red emission intensity around 657nm are similar to the green emission intensity around 545nm. The effects of temperature and concentration of ytterbium on upconversion characteristics are analyzed by rate equations in details, which match well with the experiment results.