Vol. 40, Issue 2, pp. 351-358

Abstract

Oxyhalide lead borate glasses doped with rare earth ions have been studied before and after thermal treatment. The rare earths as optically active ions were limited to the Er³⁺ ions. Near-infrared luminescence due to the main ⁴I_13/2–⁴I_15/2 laser transition of Er³⁺ was registered. The introduction of PbX₂ to the borate glass results in a reduction of spectral linewidth and an increase of luminescence lifetime of ⁴I_13/2 state of Er³⁺ ions. The unusual large spectral linewidth for ⁴I_13/2–⁴I_15/2 transition of Er³⁺ in the oxide glass host was obtained, whereas the luminescence decay from ⁴I_13/2 state is longer for a sample with PbF₂ than PbCl₂ and PbBr₂. Heat treatment introduces transformation from a glass to transparent glass-ceramic (TGC). The coordination sphere around Er³⁺ ions is changed, giving important contribution to the luminescence characteristics. The spectroscopic consequence of this transformation is the increase of luminescence lifetime and the narrowing of spectral lines of Er³⁺.