Spectroscopic properties and energy transfer mechanism in Dy3+/Tm3+ codoped fluoroaluminate glasses modified by TeO2

This paper investigates 2.9 μm emission properties and energy transfer processes in the Dy3+/Tm3+ codoped fluorotellurite glass. The measured absorption spectra demonstrate that the codoped sample can be efficiently pumped by an 800 nm excitation. Judd–Ofelt and radiative parameters are calculated and discussed. Higher spontaneous emission probability (39.6 S−1) provides a better probability to obtain laser action. Obvious 2.9 μm emission of Dy3+: 6H13/2→6H15/2 transition is observed after codoping with Tm3+ and the optimum ratio in this system is 1:1. Energy transfer processes between the two ions are discussed and the related microscopic interaction parameters are calculated. Hence, these results indicate that the Dy3+/Tm3+ codoped fluorotellurite glass is a suitable material for developing solid state laser at approximately 3.0 μm.