Shevchuk M. Phase equilibria, glass-formation regions and the properties of the intermediate phases in the systems AgGaS2+ Ge(Sn)Se2 = AgGaSe2+Ge(Sn)Se2.

Using physico-chemical analysis methods, phase equilibria in the systems AgGaS2+Ge(Sn)Se2 = AgGaSe2+ Ge(Sn)S2 were investigated for the first time. Quasi-binary phase diagrams, vertical and isothermal sections at 720 К, liquidus surface projections, spatial phase diagrams were constructed. The existence of large solid solution ranges was established. Chemical and technological conditions of the growth of AgGaGe(1+2X)S4(1-X)Se8X single crystals were developed. Structural, electric and optical properties of the single crystals were investigated. The boundaries of the glass-formation region in the germanium-containing system were determined, and the structure of the chalcogenide glassy alloys was investigated. It was shown that Er2S3 doping produced a photoluminescence maximum at 1540 nm, with its position independent on erbium concentration or the excitation wavelength. The investigation of the optical properties showed that the decrease of sulfur concentration and the increase of selenium concentration leads to the decrease of the bandgap energy from 2.83 to 2.03 eV.