Fluorescence quantum efficiency dependent on the concentration of Nd3+ doped phosphate glass

The thermal-lens (TL) method was applied to a new phosphate glass doped with Nd3+ to determine fluorescence quantum efficiency (η) and thermal properties such as: thermal diffusivity, thermal conductivity and the temperature coefficient of optical length change. Studies were performed as a function of Nd3+ concentration (0.5–3 × 1020 ions/cm3). In addition, fluorescence quenching was studied by measuring the concentration dependence of fluorescence lifetime. The TL and fluorescence lifetime results are in good agreement and corroborate the theory for energy transfer involving a pair of ions in which cross-relaxation (CR) is the dominant process.