Oxyfluoro aluminum-borate host glass: interband gap study and estimation of radiative lifetime for luminescent dopant ions

A series of new oxyfluoro aluminum-borate glasses can be used as upconversion host glass is prepared by the conventional melt-quenching technique. The effect of replacement lithium partner elements on the optoelectronic properties of the prepared glasses is studied. With increasing the ratio of LiF/LiF+Li2O the ionic character of the glass increases leading to a decrease in both of the average oscillator strength and the average interband oscillator. Fluctuation in Urbach energy is recorded which is attributed to a fluctuated structural disorder-induced broadening. The increase in LiF/LiF+Li2O molar ratio shortened the estimated radiative lifetime for luminescent dopant ions. The radiative life time decreased with decreasing the average glass molecular weight associated with an increase in the glass ion packing ratio.