Fluorescence intensity ratio technique and its reliability
Vishab Kesarwani, Vineet Kumar
Abstract
Abstract The present article reports the optical absorption and upconversion (UC) studies of 1.0 mol% Er 3+ /2.0 mol% Yb 3+ doped/codoped glasses prepared by melt-quenching technique. The elements present and the composition of the prepared glass have been confirmed from XPS and XRF analysis respectively. Judd-Ofelt intensity parameters have been calculated using the absorption spectrum which is further utilized to predict the nature of Er _ O bond, the transition probabilities, branching ratios and radiative lifetimes. The CIE study shows non-colour tunable and highly pure green emission (94.2%). The temperature-dependent UC emission spectra of the 2.0 mol% Yb 3+ sensitized glass have been recorded at three different pump power densities to establish a reliable FIR based temperature scale. Furthermore, the Arrhenius fitting of the temperature-dependent spectra reveals low thermal quenching of green luminescence in the codoped glass.