4f–4f intensities of the Tm3+ ions in fluoroindate glasses: the influence of third-order effects through odd intensity parameters

Abstract

In this work an analysis of the phenomenological Ωλ intensity parameters for the Tm3+ ion in fluoroindate glass is made using the standard Judd–Ofelt theory, and a modified oscillator strength taking into account odd-order contributions is utilized. Different sets of phenomenological intensity parameters Ωλ (λ=1,2,3,4,5,6) are discussed. The set of better quality is used to analyze the influence of third-order effects through odd intensity parameters in the new approximation. Fluoroindate glasses of compositions (40−x)InF3–20ZnF2–20SrF2–16BaF2–2GdF3–2NaF–xTmF3 with x=1, 2 and 3 mol% were prepared, and the absorption spectra at room temperature in the spectral range from 300 to 2500 nm were obtained. The experimental oscillator strengths determined from the area under the absorption band are compared to the calculated ones.