掺铒锆钛酸铅镧陶瓷的上转换动力学分析

Analysis of the dynamics of upconversion in erbium-doped transparent lead lanthanum zirconate titanate ceramic

测量了掺铒锆钛酸铅镧(Er3+:PLZT)陶瓷的吸收光谱和上转换荧光光谱,利用Er3+:PLZT的吸收光谱,计算Er3+离子的辐射跃迁概率.分析了980nm激发下Er3+:PLZT的上转换荧光光谱,观察到明显的上转换荧光,且峰值位于540,564nm附近的绿色荧光带比678nm附近的红色荧光带强.建立了Er3+离子跃迁的速率方程,通过求解速率方程并采用拟合荧光衰减实验曲线的方法,得出Er3+:PLZT的频率上转换系数C22=0.91×10-18cm3/s,C33=18.23×10-18cm3/s.分析表明,Er3+:PLZT透明陶瓷中4I11/2能级上的Er3+离子较容易发生频率上转换.

The absorption and upconversion fluorescence spectra of Er^3＋ ions in Er^3＋ doped transparent lead lanthanum zirconate titanate（PLZT） ceramic were measured at room temperature. The radiative transition probabilities of the Er^3＋ ions were calculated using the absorption spectrum of Er^3＋ doped PLZT. Strong upconversion emission was observed in the upconversion luminescence Of Er^3＋ doped PLZT. The green emission intensities at 540 nm and 564 nm were stronger than the red emission intensity at 678 nm. The upconversion rate equations describing the dynamic process of the system have been deduced. The upconversion coefficients were estimated by numerically solving the rate equations and fitting the simulated curves to the measured data. The coefficients C22and C33 obtained are 0.91 × 10^-18 cm^3/s and 18.23× 10^-18 cm^3/s, respectively. The results show that evident upconvesion phenomenon can be observed in Er^3＋ ： PLZT transparent ceramics, which is consistent with our observation.