Ce^(3+)对Er^(3+)/Yb^(3+)共掺TeO_2-WO_3-ZnO玻璃发光性能的影响

Effect of introducing Ce^(3+) on the emission properties of Er^(3+)/Yb^(3+)-doped TeO_2-WO_3-ZnO glasses

在Er^(3+)/Yb^(3+)共掺TeO2-WO3-ZnO玻璃中引入Ce^(3+),研究了Ce^(3+)对Er^(3+)1·5μm发射性能及其上转换发光性能的影响。结果表明,随Ce^(3+)浓度的增加Er^(3+)1·5μm波段的荧光强度先增强后降低,优化的Ce^(3+)掺杂浓度在2·07×10^(20)/cm3左右;1·5μm波段的荧光寿命则随Ce^(3+)浓度的增加有轻微降低,从3·4ms降到3·0ms,但Ce^(3+)浓度的增加对1·5μm波段的荧光半高宽基本无影响;Er^(3+)/Ce^(3+)间的交叉弛豫Er^(3+)(4I11/2)+Ce^(3+)(2F5/2)→Er^(3+)(4I13/2)+Ce^(3+)(2F7/2)使玻璃的上转换发光强度大大降低,但在过高的Ce^(3+)浓度下,Er^(3+)/Ce^(3+)间的另一交叉弛豫Er^(3+)(4I13/2)+Ce^(3+)(2F5/2)→Er^(3+)(4I15/2)+Ce^(3+)(2F7/2)则使Er^(3+)4I13/2能级粒子数减少,导致1·5μm波段荧光强度和荧光寿命降低.

Ce^3＋ ions were introduced into the Er^3＋/Yb^3＋ -codoped TeO2-WO3-ZnO glasses, and the effect of Ce^3＋ on the emission properties at 1.5μm band and the upconversion luminescence of Er^3＋ in the glasses was investigated. With the increasing of Ce^3＋ concentration, the emission intensity of Er^3＋ at 1.5μm band increases firstly, and then decreases. The optimal doping concentration of Ce^3＋ is about 2.07 ×10^20/cm^3 . As for the Er^3＋ emission at 1.5μm band, the fluorescence lifetime decreases a little from 3.4ms to 3.0ms, while the full width at half maximum （FWHM） hardly changes with the increase of Ce^3＋ concentration. Due to the effective cross relaxation between Ce^3＋ and Er^3＋ ： Er^3＋（^4I11/2）＋Ce^3＋（^2F5/2）→Er^3＋（^4I13/2）＋Ce^3＋（^2F7/2）, the upconversion emission intensity of Er^3＋ is reduced greatly. But when Ce^3＋ -doping concentration is too high, the other cross relaxation between Ce^3＋ and Er^3＋ ： Fr^3＋（^4I13/2）＋Ce^3＋（^2F5/2）→Er^3＋（^4I15/2）＋Ce^3＋（^2F7/2） happens, which depopulates the ^4I13/2 level of Er^3＋ and results in the decrease of the emission intensity and fluorescence lifetime of Er^3＋ at 1.5μm band.