Near-infrared quantum cutting luminescence in Pr³⁺/Yb³⁺ doped lead bismuth borate glass

In this paper, thermally stable lead-bismuth-borate glasses were doped with 0.5 mol% of Pr³⁺ ions at several concentration levels of Yb³⁺ ions. Structural characterizations were performed via Raman, differential scanning calorimetry, optical absorption and fluorescence spectra. The Judd-Ofelt intensity parameter, [Formula: see text], of Pr³⁺ doped glass was comparatively higher than those from reported ones, which reflects the increase of co-valency and asymmetry of chemical bonds in the local environment of Pr³⁺. Near-infrared emission in 900-2200 nm wavelength range was recorded through 443 nm blue laser pumping. Visible to near-IR quantum cutting and concentration quenching mechanisms were discussed to understand the luminescent behaviour. Intense IR emission ([Formula: see text] features generated by absorbing one visible photon leads to quantum efficiencies close to 128% in Pr³⁺/Yb³⁺ co-doped samples which may improve the solar spectrum absorption and accordingly, increase the efficiency of c-Si solar cells. Emission cross-section, lifetime, figure of merit and gain bandwidth corresponding to Pr³⁺: [Formula: see text] ([Formula: see text]m) were comparatively reported suggesting that the glass with molar composition 0.5Pr³⁺/0.1Yb³⁺ might be a potential candidate for [Formula: see text]m laser operation with low pump threshold.