掺铒矾酸钇晶体上转换荧光研究

使用波长为808和658nm的半导体激光器和染料激光器作为激发源，测量了Er³⁺：YVO₄晶体的波长在553和410nm附近的上转换荧光.对激发过程的分析表明，贡献于上转换荧光的主要激发机制为激发态吸收.在不同浓度下对上转换荧光的寿命测量结果显示，随Er³⁺浓度的提高，553nm绿光的荧光寿命随浓度的增加而减小，但410nm的荧光寿命随Er³⁺浓度无明显变化.结合绿光强度随掺杂浓度增加而减小的结果，认为在所测浓度范围内关键词：

STUDY ON UPCONVERSION FLUORESCENCE OF Er3+-DOPED YTTRIUM VANADATE

Upconversion fluorescence near 553 and 410nm was detected when the Er³⁺-doped yttrium vanadate (Er³⁺∶YVO₄) crystal was excited with a 808nm-diode laser and a 658nm-dye laser. Analysis of excitation mechanism shows that excited state absorption dominantly contributes to the upconversion emissions. Measurement of lifetimes for different Er³⁺ concentration indicates that the lifetime of 553nm emission decreases with increasing Er³⁺ concentration, but no considerable changes of that of 410nm emission have been observed. With the consideration of the fact that the intensity of 553nm band declines with increasing Er³⁺ concentration, we argue that in the concentration range measured there is an appreciable concentration quenching in the 553nm emission, and a dominant population channel of its upper state (⁴S_3/2) is the nonradiative relaxation from the upper state (²H_9/2) of the 410nm band.