Spectroscopic and laser properties of Ho3+ doped lanthanum‐tungsten‐tellurite glass and fiber

The spectroscopic properties of 2-mu m emission in Ho3+-doped lanthanum-tungsten-tellurite glasses with different Ho2O3 concentrations were investigated. The strongest emission was observed in a glass sample doped with 0.5 mol% Ho2O3, with a fluorescence lifetime of 3.16 ms and a emission cross section of 6.97 x 10(-21) cm(2) at 2040 nm. For this composition, no obvious changes in the emission properties and fluorescence lifetime were observed at temperatures of 295-350 K. Using this 60TeO(2)-30WO(3)-9.5La(2)O(3)-0.5Ho(2)O(3) glass as a core material, Ho3+-doped double cladding fiber with a core diameter of 14 pm and a numerical aperture of 0.12 was developed. A maximum laser output power of 34 mW at 2040 nm was achieved with a 9-cm-long Ho3+-doped tellurite glass fiber. To the best of our knowledge, this study presents the first report on the 2-mu m laser output from a Ho3+-doped tellurite oxide glass fiber resonantly pumped by a 1.94 mu m Tm-fiber laser. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.