Effect of Ga incorporation in the As30Se50Te20 glass

• 1 at.% of Ga addition was introduced in As30Se50Te20 glass without crystallization.
• Ga1As29Se50Te20 glass could be used for rare earth doping and fiber drawing.
• Ga additions over 2 at.% in As30Se50Te20 glass provokes strong crystallization.
• Extraction mainly of cubic Ga2Se3 polymorphs with Ga addition in As30Se50Te20 glass.
• Crystallized As28Ga2Se50Te20 is expected to be useful for controlled ceramization.

The effect of Ga addition on the physical properties and structure of As30 − xGaxSe50Te20 alloys is studied using atomic density measurements, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy with energy-dispersive spectroscopy, optical spectroscopy in visible and IR regions, as well as extended X-ray absorption fine structure techniques. The process of As30Se50Te20 glass crystallization owing to Ga additives (1–10 at.%) is shown to be related to extraction of droplet-like nanoinclusions in As28Ga2Se50Te20 glassy-like alloy and larger microcrystallites basically with a structure of cubic Ga2Se3 polymorphs as observed for As25Ga5Se50Te20 and As20Ga10Se50Te20. It was possible to introduce only 1 at.% of Ga (substituting As) without essential crystallization within the studied system. This glass was successfully drawn into fiber and can be used for rare earth doping. The microcrystalline seeds present in As28Ga2Se50Te20 alloy can serve as a basis for further development of crystallization-controlled ceramization to produce high-reliable far-IR transmitting media.