Thermal stability and Judd-Ofelt analysis of optical properties of Er3+-doped tellurite glasses
(School of Materials Science and Engineering, Central South University, Changsha 410083, China)
Abstract: Er3+-doped TeO2-ZnO-Na2O-B2O3-GeO2 (TZNBG) glasses were prepared by melt-quenching method. Differential scanning calorimetry (DSC) and thermal mechanical analysis (TMA) were used to calculate thermal parameters: crystallization temperature (Tx), glass transition temperature (Tg) and thermal expansion (α). Besides, Judd-Ofelt theory is applied to analyzing absorption spectra. Intensity parameters Wλ (λ=2, 4, 6), transition probabilities Aed, radiative lifetime τi, and branching ratios β of Er3+ transitions were obtained. Emission cross-section σemis of 4I13/2→4I15/2 transition of Er3+ was calculated according to the theory of McCumber. All of the parameters indicate that the thermal stability and optical properties of Er3+-doped TZNBG glasses are improved effectively.
Key words: tellurite glasses; thermal stability; Judd-Ofelt theory; spectroscopic properties