用熔融法制备了Er^3+/Yb^3+共掺TeO2-GeO2-Bi2O3-K2O玻璃样品,对玻璃进行了差热分析并测试了玻璃的吸收光谱和上转换光谱,应用Judd-Ofelt理论计算了Er^3+/Yb^3+共掺锗碲铋钾玻璃的3个强度参数,及Er^3=各能级的振子强度、自发辐射跃迁几率、荧光分支比和辐射寿命等光谱参数.通过977nm的激光二极管抽运,在室温下同时观察到绿色(522和546nm)和红色(658nm)的荧光发射,分别是由于Er^3+自^2H11/2→^4I15/2、^4S3/2→^4I15/2和^4F9/2→^4I15/2跃迁而产生,强烈的绿光和红光发射均来源于双光子吸收过程.
A kind of Er^3+/Yb^3+ co-doped TeO2-GeO2-Bi2O3-K2O glass was fabricated by means of the melting method, and the absorption and upconversion spectra of the glass were obtained by differential thermal analysis. Judd-Ofelt theory was then used to calculate the three strength parameters of the glass, the oscillator strength, the spontaneous radiated transition probability, the fluorescence-branching ratio and the radiation life of each energy level of Er^3+. Moreover, the green fluorescent emissions centering at 522 and 546 nm and the red fluorescent emission at 658 nm were obtained under the laser diode excitation at 977 nm, which respectively corresponded to the ^2H11/2→^4I15/2、^4S3/2→^4I15/2and^4F9/2→^4I15/2 of Er^3+ .It is found that the strong green and red emissions all result from a two-photon absorption process.