Neodymium-doped germanotellurite glasses for laser materials and temperature sensing

GTSN: Nd (GeO2-TeO2-SrF2-Nb2O5–Nd2O3) glasses of varying (0.2–3%) Nd concentration were obtained using the melt-quenching method. Their thermal properties were evaluated using differential scanning calorimetry, showing highly favorable glass thermal stability. Glass structure was analyzed using XRD, IR and Raman spectroscopy. Combining the advantages of germanate, tellurite and fluoride optical systems, a promising glass laser material was achieved, as proven with optical spectroscopy methods, such as absorption, emission and fluorescence lifetime spectroscopies. Utilizing the fluorescence intensity ratios between emission bands from Nd excited levels, several models for luminescent thermometry were established for GTSN: Nd. One of the models was tested in a laser power-dependence experiment, allowing to estimate temperature increase during high power optical excitation. Great thermal stability and spectroscopic performance of the material, along with a built-in method for contactless temperature measurement, make GTSN: Nd a promising material for glass-based optically active elements. [Display omitted] •High thermal stability of novel GTSN germanotellurite glasses.•Influence of dopant concentration on thermal and spectroscopic properties.•Significant peak emission cross-section of 2.08 × 10−20 cm2 at 1060 nm.•Four temperature sensing models based on NIR Nd fluorescence intensity ratios.•Luminescent thermometry model tested out in practical conditions.