Structure, luminescence and energy transfer of fluoroindate glasses co-doped with Er3+/Ho3+

This work reports on the analysis of structural and spectroscopic properties of the fluoroindate glasses co-doped with Er3+/Ho3+. Structural analysis showed that erbium and holmium ions were modifier ions and depolymerizedof the fluoroindate glass network. The energy transfer processes between rare - earth ions in fluoroindate glasses pumped by and 980 nm laser diode have been also examined. Due to partial Er3+ → Ho3+ energy transfer and superposition of Er3+: 4I11/2 → 4I13/2 (2.77 μm)+ Ho3+: 5I6 → 5I7 (2.85 μm) radiative transitions in fluoroindate glass co-doped with 0.8ErF3/1.6HoF3, a broadening 3 μm luminescence (Δλ= 201 nm) was obtained. The overall energy transfer efficiency ηET1 + ηET2 was calculated to be 95% indicating efficient sensitization of the holmium ions by erbium.