Spectroscopic and thermal study of a new glass from TeO2Ga2O3GeO2 system

Tellurium oxide and germanium oxide based glasses are classified as the heavy metal oxide glasses, with phonon energies below 880 cm−1. These glasses transmit to longer wavelengths when compared to borate, phosphate and silicate glasses because of the heavier mass of germanium. In this paper we present a new promising TeO2Ga2O3GeO2 glasses with high thermal stability and good optical properties in the near and mid-IR regions. The glass can be easily obtained for the wide range of Te/Ge ratio, which gives opportunity to engineering desirable properties. Based on the FT-IR spectra it could be stated that the tellurite network is monotonically transformed into germanate one as the GeO2 content increases. Admixtures of GeO2 into the network of tellurite glass causes the conversion of [TeO4] to [TeO3] units. Thus, the network of the glass could be consider as a mixture of the [TeO4], [TeO3] and [GeO4] units and with Ga3+ ions playing the role of its modifier. The glasses demonstrate high transmittance in mid-IR up to 6 μm what makes these materials suitable for mid-IR applications.