Fluoroindate glasses co-doped with Pr3+/Er3+ for near-infrared luminescence applications

Abstract

Fluoroindate glasses co-doped with Pr³⁺/Er³⁺ ions were synthesized and their near-infrared luminescence properties have been examined under selective excitation wavelengths. For the Pr³⁺/Er³⁺ co-doped glass samples several radiative and nonradiative relaxation channels and their mechanisms are proposed under direct excitation of Pr³⁺ and/or Er³⁺. The energy transfer processes between Pr³⁺ and Er³⁺ ions in fluoroindate glasses were identified. In particular, broadband near-infrared luminescence (FWHM = 278 nm) associated to the ¹G₄ → ³H₅ (Pr³⁺), ¹D₂ → ¹G₄ (Pr³⁺) and ⁴I_13/2 → ⁴I_15/2 (Er³⁺) transitions of rare earth ions in fluoroindate glass is successfully observed under direct excitation at 483 nm. Near-infrared luminescence spectra and their decays for glass samples co-doped with Pr³⁺/Er³⁺ are compared to the experimental results obtained for fluoroindate glasses singly doped with rare earth ions.