Investigation of mid-infrared emission characteristics and energy transfer dynamics in Er3+ doped oxyfluoride tellurite glass

摘要

Er³⁺ doped oxyfluoride tellurite glasses have been prepared. Three Judd-Ofelt parameters Ωt (t = 2, 4, 6) and radiative properties are calculated for prepared glasses. Emission characteristics are analyzed and it is found that prepared glasses possess larger calculated predicted spontaneous transition probability (39.97 s⁻¹), emission cross section σem (10.18 × 10⁻²¹ cm²) and σem × Δλeff (945.32 × 10⁻²⁸ cm³), corresponding to the 2.7 μm emission of Er³⁺: ⁴I11/2→ ⁴I13/2 transition. The results suggest that the prepared glasses might be appropriate optical material for mid-infrared laser application. Moreover, rate equation analysis which is rarely used in bulk glass has been carried out to explain the relationship between emission intensity and Er³⁺ concentration. The calculation results show that with the increment of Er³⁺ concentration, the energy transfer up-conversion rate of ⁴I13/2 state increases while the rate of ⁴I11/2 state reduces, resulting in the change of 2.7 μm emission.