Concentration dependence of the optical properties of glassy alloys in the HgS-Ga2S3-GeS2 system

The concentration dependences of the optical properties of glassy alloys in the HgS-Ga2S3-GeS2 system have been investigated in the spectral range 2.0-2.9 eV. The energy gap E (g) of glasses has been estimated, and the dependence of the energy gap on the content of HgS and Ga2S3 has been analyzed. The spectral dependences alpha(h nu) for glasses in the system under investigation in the fundamental absorption range are described by the Urbach rule. The alloys containing a parts per thousand yen 20 mol % (HgS + Ga2S3) are characterized by an ordering and a decrease in the energy gap E (g) , which are explained by the changes in the short-range order in the arrangement of the atoms involved in the composition of alloys. It has been assumed that, at high concentrations of modifiers, there can arise microscopic inclusions, i.e., different defects, which can scatter light and decrease the transparency of glassy alloys.