Effect of network modifiers on spectroscopic properties of erbium-doped phosphate glasses

Abstract

The integrated absorption cross section Σ_abs, peak emission cross section σ_emi, Judd-Ofeld intensity parameters Ω_t (t=2,4,6), and spontaneous emission probability A_rR of Er³⁺ ions were determined for Erbium doped alkali and alkaline earth phosphate glasses. It is found the compositional dependence of σ_emi is almost similar to that of Σ_abs, which is determined by the sum of Ω_t(3Ω₂ + 10Ω₄ + 21Ω₆). In addition, the compositional dependence of Ω_t was studied in these glass systems. As a result, compared with Ω₄ and Ω₆, the Ω₂ has a stronger compositional dependence on the ionic radius and content of modifiers. The covalency of Er-O bonds in phosphate glass is weaker than that in silicate glass, germanate glass, aluminate glass, and tellurate glass, since Ω₆ of phosphate glass is relatively large. A_R is affected by the covalency of the Er³⁺ ion sites and corresponds to the Ω₆ value.

Keywords

erbium doped phosphate laser glasses / spectroscopic properties / network modifiers / compositional dependence

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