First Ga2Se3 infrared transparent chalcogenide ceramics

Abstract

Fully dense infrared (IR) transparent chalcogenide ceramics were obtained from densification of Ga₂Se₃ crystalline powder by Spark Plasma Sintering (SPS) under vacuum. Promising results were attained such as a maximum transmission of 63 % at λ = 11 µm, close to the maximum value of transmittance previously measured for single crystals, a wide transparency spectral range (4–16 µm), and a refractive index of 2.58 at λ = 1.55 µm. Electron Back Scattered Diffraction (EBSD) was used to elucidate grain microstructure, showing randomly oriented particles and a bimodal grain size distribution. These ceramics exhibit expected mechanical properties for selenide materials with a Vickers hardness of 287 kg/mm² and a Young’s modulus of 52 GPa.