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

Er(3+) 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)cm(2)) and σem × Δλeff (945.32 × 10(-28)cm(3)), corresponding to the 2.7 μm emission of Er(3+): (4)I11/2→ (4)I13/2 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 Er(3+) concentration. The calculation results show that with the increment of Er(3+) concentration, the energy transfer up-conversion rate of (4)I13/2 state increases while the rate of (4)I11/2 state reduces, resulting in the change of 2.7 μm emission.