Germanotellurite glasses doped with ytterbium and neodymium - Their spectroscopic properties and thermometric capability

Abstract

Germanotellurite glasses doped with Yb and co-doped with Nd and Yb were produced using the melt-quenching method. Their spectroscopic properties were analyzed at 300 K and at elevated temperatures up to 725 K in terms of their luminescent qualities and application potential in luminescence thermometry. The Nd–Yb transfer dynamics were discussed. Owing to the efficient energy transfer from Nd to Yb ions, a temperature sensing model based on the intensity between emission bands from 4F5/2 (Nd) and 2F5/2 (Yb) levels was established, reaching around 0.7%/K of relative sensitivity. Straight after, the model was successfully tested in practical spectroscopy lab conditions to estimate the temperature increase resulting from high power laser diode excitation. Glass spectroscopic features, in conjunction with an intrinsic method for fast and contactless temperature readout, make GTSN: Nd, Yb a promising material especially for optical temperature sensors.