| The optical properties of Ni2+-doped barium-indium-gallium-based (BIGaZYT) and lead-based (PBI) fluoride glasses have been investigated. Absorption and luminescence measurements performed over a wide temperature range indicate that the dopant ion occupies a site of nearly-octahedral symmetry. We observe three luminescence transitions (green, red and NIR) which are assigned to the [MATH] and [MATH] transitions of the Ni2+ ion. Steady-state emission spectra and luminescence decay times as a function of temperature have been measured to determine the presence and extent of nonradiative transitions. In order to correlate glass-matrix composition with emission spectral properties, detailed time resolved measurements have been performed. |