The transparent Ga2 O3-GeO2-Na2 O glasses doped with Tm3 + / Er3 + / Yb3 + were prepared by melting quenching method. The effects of Tm2 O3 contents on the visible and infrared spectra of the samples under 808 and 980 nm excitation were compared. The mechanisms of energy transfer between Tm3 + , Er3 + and Yb3 + ions were analyzed combining with the energy level of rare earth ions. The re-sults show that the obvious blue (473 nm), red (655 nm), green (521 and 544 nm) emission can be observed in Tm3 + / Er3 + / Yb3 + -codoped sample. I1. 8 / I1. 53 (intensity ratio of Tm3 + :1 800 nm and Er3 + :1 530 nm) are enhanced and the red and green upconversion emission intensities under the excitation of 808 nm are adjusted due to the efficient energy transfer between Er3 + and Tm3 + with the increase of Tm3 + concentration. Correspondently, the emission intensity of 473, 521 and 655 nm show a trend of firstly increasing and then decreasing, and achieve the maximum value when the mole fraction of Tm2 O3 is up to 0. 3% . The upconversion red, green and blue emission intensity under 980 nm excita-tion is higher than that of 808 nm because of the sensitizing effect of Yb3 + to Er3 + and Tm3 + .%采用熔融淬冷法制备得到透明的 Tm3+／ Er3+／ Yb3+掺杂镓锗钠玻璃。对比研究了808 nm 和980 nm 激发下 Tm2 O3含量对样品可见-红外光学光谱特性的影响。结合稀土离子能级结构,分析了 Tm3+、Er3+和 Yb3+离子之间的能量传递机制。结果表明：在808 nm 和980 nm 的激发下,Tm3+／ Er3+／ Yb3+掺杂样品中均观察到了473,655,521,544 nm 的蓝、红和绿光。在808 nm 激发下,随着 Tm3+浓度的增加,Tm3+：1800 nm 和 Er3+：1530 nm发射强度的比率 I1.8／ I1.53逐渐增大。由于在 Tm3+和 Er3+间的能量传递有效地改变了红光和绿光的发射强度,473,521,655 nm 的发光强度呈现先升高再降低的趋势,在 Tm2 O3掺杂摩尔分数为0.3％时达到最大值。而在980 nm 激发下,由于 Yb3+对 Er3+和 Tm3+的能量传递起主要作用,使得其上转换红光(655 nm)、绿光(521 nm 和544 nm)和蓝光(473 nm)的发光强度高于808 nm 激发下的上转换发光。
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