AUTHOR=Yuan Jian , Wang Weichao , Ye Yichen , Deng Tingting , Ou Deqian , Cheng Junyang , Yuan Shengjin , Xiao Peng 

TITLE=Effect of BaF2 Variation on Spectroscopic Properties of Tm3+ Doped Gallium Tellurite Glasses for Efficient 2.0 μm Laser

JOURNAL=Frontiers in Chemistry

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2020.628273

DOI=10.3389/fchem.2020.628273

ISSN=2296-2646

ABSTRACT=<p>The effects of substitution of BaF<sub>2</sub> for BaO on physical properties and 1. 8 μm emission have been systematically investigated to improve spectroscopic properties in Tm<sup>3+</sup> doped gallium tellurite glasses for efficient 2.0 μm fiber laser. It is found that refractive index and density gradually decrease with increasing BaF<sub>2</sub> content from 0 to 9 mol.%, due to the generation of more non-bridging oxygens. Furthermore, OH<sup>−</sup> absorption coefficient (α<sub>OH</sub>) reduces monotonically from 3.4 to 2.2 cm<sup>−1</sup> and thus emission intensity near 1.8 μm in gallium tellurite glass with 9 mol.% BaF<sub>2</sub> is 1.6 times as large as that without BaF<sub>2</sub> while the lifetime becomes 1.7 times as long as the one without BaF<sub>2</sub>. Relative energy transfer mechanism is proposed. The maximum emission cross section and gain coefficient at around 1.8 μm of gallium tellurite glass containing 9 mol.% BaF<sub>2</sub> are 8.8 × 10<sup>−21</sup> cm<sup>2</sup> and 3.3 cm<sup>−1</sup>, respectively. These results indicate that Tm<sup>3+</sup> doped gallium tellurite glasses containing BaF<sub>2</sub> appear to be an excellent host material for efficient 2.0 μm fiber laser development.</p>