中文摘要：

研究了提拉法生长的Er^3＋／Yb^3＋：Gd3Sc2Ga3O12和Er^3＋：Gd3Sc2Ga3O12晶体在室温下320—1700nm范围的吸收光谱和500-750nm范围内的上转换荧光谱，同时对其上转换荧光的可能发生机制、途径以及上转换过程可能对Er^3＋的2．8μm波段激光振荡产生的影响进行了分析和讨论．结果表明：Yb^3＋的敏化显著地增强了晶体在966nm附近的吸收能力，大幅度加宽了晶体在该处的吸收带宽．在940nm激光的激发下，Er^3＋／Yb^3＋：Gd3Sc2Ga3O12中的上转换荧光强度明显强于Er^3＋：Gd3Sc2Ga3O12中的上转换荧光强度，表明Yb^3＋与Er^3＋之间存在高效率的能量传递，其主要上转换机制可能为Yb^3＋-Er^3＋，Er^3＋-Er^3＋能量传递．

英文摘要：

Er^3 ＋/Yb^3 ＋ ： Gd3 Sc2 Ga3 O12 and Er^3 ＋ ： Gd3 Sc2 Ga3 O12 crystals have been grown by Czochralski method. The absorption spectra from 320 to 1700 nm and the up-conversion flttoreseence spectra from 500 to 750 nm of them were investigated at room temperature, respeetively. The possible up-eonversion lumineseenee mechanisms in Er^3＋/Yb^3＋ -eodoped crystals and their influences on the 2.8μm laser emission were discussed. Experimental results show that the absorption of Er^3 ＋ ：Gd3 Sc2Ga3 O12 around 966 nm and its bandwidth are remarkably increased by Yb^3 ＋ sensitizing. Under 940 nm excitation, the up-conversion luminescence intensity of Er^3＋/Yb^3＋ ：Gd3Sc2Ga3O12 is much stronger than that of Er^3＋ ：Gd3Se2Ga3O12. It demonstrates that there exist effective energy transfer processes between Yb^3 ＋ and Er^3 ＋ , and the dominant mechanism of up-conversion may be the energy transfer processes of Yb^3 ＋ -Er^3 ＋ and Er^＋ -Er^3 ＋ .