Study on the optical and thermal properties of a new mid-infrared TeO2-Ta2O5-La2O3 glass

Abstract

A new mid-infrared tellurite ternary glass with small glass formation area was prepared by modified melt quenching. A high-throughput, simple and fast glass melting process is realized by erecting the tube furnace sideways. The forming range of glass can be quickly and efficiently explored. Moreover, the equipment is convenient for stirring in the melting process, and can effectively reduce bubbles and stripes in the molten glass, thus preparing the matrix glass with excellent performance. The maximum phonon energy of the glass is 765 cm−1, and the appropriate phonon energy is beneficial to achieve intense mid-infrared luminescence or laser. The density of glass is 5.385 g/cm3, indicating high refractive index of this new glass. The glass transition temperature is 428 °C, and there is no obvious crystallization thermal effect before the glass melts. The thermal expansion coefficient of TeO2-Ta2O5-La2O3 (TTL) glass is 12.5 × 10−6K−1 (25–300 °C). The refractive index of glass is 2.01 and the Abbe number is 21.48. The maximum transmittance in the near infrared range is between 76.44% and 80.85%, while the theoretical transmittance is 80.08% (2700 nm). Therefore, this glass is a promising laser glass matrix material in the 2.0–2.7 μm band.