Band assignments in absorption and photoluminescence of a new transparent fluoroindate glass doped with Er and Yb

Fluoroindate glasses containing 1, 2 and 3, ErF3+YbF3 mol% were prepared in a dry box under argon atmosphere. The optical absorption and photoluminescence spectra have been measured as a function of the temperature in the range from 15 to 300 K. The absolute intensities of the transitions observed in the optical spectra have been interpreted in terms of transitions within 4fN configurations. The energy matrices resulting from the combination of free-ion terms with the crystal field were diagonalized. Excellent correlations were obtained between experimental transition energies and computed level structures. Phenomenological Ωλ intensity parameters for Er+3and Yb+3 ions in fluoroindate glass were also calculated using the standard theory of Judd–Ofelt. Good agreement was obtained between the experimental oscillator strengths determined from the area under the absorption band and the calculated ones. The splitting of the Er+3 ground state was determined from the analysis of photoluminescence spectra.