Enhanced frequency upconversion in Er 3+ doped fluoroindate glass due to energy transfer from Tm 3+

Abstract

Energy transfer processes between Er 3+ and Tm 3+ were investigated examining the frequency upconversion emissions in a fluoroindate glass pumped at 790 nm. A 60-fold enhancement in the emission at ≈670 nm originating from Er 3+ was observed when Tm 3+ at concentration of 2% was introduced in a sample containing 2% of Er 3+. The results are explained considering the influence of cross-relaxation processes between the active ions.