Li^+对硅酸盐玻璃中Yb^(3+)、Tm^(3+)上转换效率的影响

Effect of Lithium Ion on The Up-conversion Efficiency of Yb^(3+) and Tm^(3+) in Silicate Glass

利用高温熔融法制备了不同Li^+含量的掺杂Yb^(3+)、Tm^(3+)的硅酸盐玻璃样品,玻璃样品在980 nm半导体激光器的泵浦下能够产生477 nm的蓝光和654 nm的红光。由上转换的荧光强度和泵浦功率的双对数拟合直线得到,添加Li^+能够增加上转换过程中Tm^(3+)向上跃迁的几率,Tm^(3+)的3F2和1G4能级的粒子数布居增加,从而提高辐射跃迁的几率。红外光谱和拉曼光谱表明Li^+的添加对玻璃基质的声子能量影响不大,却使得声子态密度减小,使上转换效率提高,从而提高Yb^(3+)、Tm^(3+)在硅酸盐玻璃中的发光强度。

Yb^3＋ and Tm^3＋co-doped silicate glasses with different contents of Li＋were prepared by high temperature melting,which could emit 477 nm blue and 654 nm red light under 980 nm LD pumping.The double logarithmic linear fitting of light emission intensity and pump power show that the probability of Tm^3＋upward transition in up-conversion process increases after the adding of Li＋because of the number of electrons populated at ^3F2 and ^1G4 energy levels of Tm^3＋ increasing,which leads to improving the probability of radiation transition.The infrared spectra and Raman spectra show that the addition of Li＋has little effect on phonon energy of the glass substrate,however,the density of phonon states decreases.Finally,the luminescence intensity of Yb^3＋ and Tm^3＋in silicate glass is improved by increasing the up-conversion efficiency.