Energy transfer characteristics of silicate glass doped with Er3+, Tm3+, and Ho3+ for ∼2 μm emission

Abstract

A Er3+/Tm3+/Ho3+ tri-doped silicate glass with good thermal stability is prepared by melt-quenching method. Efficient ∼2 μm emission is observed under 808 nm laser excitation. It is found that the 2.0 μm emission of Ho3+ can be enhanced under the excitation at 808 nm by incorporating Er3+ and Tm3+. Based on the measurement of absorption spectra, the Judd–Ofelt intensity parameters, radiation emission probability, and branching ratio are calculated to evaluate the spectroscopic properties simultaneously. The maximum value of emission cross section of Ho3+ is 3.54 × 10−21 cm2 at 2008 nm. Additionally, the phonon assistance and the micro-parameters in the energy transfer process are quantitatively analyzed by using Dexter model. The energy transfer coefficient from Tm3+ to Ho3+ can reach as high as 21.44 × 10−40 cm6/s, respectively. The emission property together with good thermal property indicates that Er3+/Tm3+/Ho3+ tri-doped silicate glass is a potential kind of laser glass for efficient 2 μm laser.