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 Ω_t (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 σ_em (10.18?×?10?21?cm2) and σ_em?×?Δλ_eff (945.32?×?10?28?cm3), corresponding to the 2.7?μm emission of Er3+: 4I_11/2→?4I_13/2 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 4I_13/2 state increases while the rate of 4I_11/2 state reduces, resulting in the change of 2.7?μm emission.