Upconversion luminescence in tellurite glass codoped with Yb~(3+)/Ho~(3+) ions

摘要

The optical properties of Yb~(3+)/Ho~(3+) - codoped tellurite glass has been investigated. Upconversion luminescence at the wavelengths of 545 nm (~5S_2 (~5F_4) → ~5I_8) and 654 nm (~5F_5 → ~5I_8) in holmium was obtained as a result of energy transfer between Yb~(3+) and Ho~(3+) ions. The optimization of the activator content and the concentration ratio were conducted with the purpose of maximizing the efficiency of energy transfer. Mechanism and energy diagram involved in observed emission were discussed. The highest upconversion emission intensity was obtained in the tellurite glass codoped with 0.5Yb_2O_3/0.1Ho_2O_3 molar ratio.