Investigation of 2.0 μm emission in Tm 3+ and Ho 3+ co-doped TeO 2–ZnO–Bi 2O 3 glasses

Abstract

Tm 3+ and Ho 3+ co-doped TeO 2–ZnO–Bi 2O 3 (TZB) glasses were prepared by the conventional melt-quenching method. Two micrometre emission properties of the TZB glasses exited by 808 nm Laser Diode (LD) were analyzed and discussed. The Judd–Ofelt parameters, spontaneous radiative transition probabilities and radiative lifetime of Ho 3+ were calculated based on the absorption spectra by using Judd–Ofelt theory. The absorption spectra and fluorescence spectra were measured. The predicted spontaneous radiative transition rate of 5I 7 → 5I 8 of Ho 3+ is as high as 466.8 s −1. The result of fluorescence spectra indicates that the maximum emission intensity of Ho 3+ 2.0 μm and of Tm 3+ 1.47 μm emission can be achieved at the concentration of 1 mol% Tm 2O 3 and 1 mol% Ho 2O 3 in TZB glasses. The maximum absorption and emission cross-section of Ho 3+ near 2.0 μm are 0.87 × 10 −20 cm 2 at 1951 nm and 1.07 × 10 −20 cm 2 at 2047 nm, respectively.