Threshold behaviours in GexAs10Se90-x and GexSb10Se90-x glasses

Abstract

We investigated the effect of the elemental substitution of As by Sb on the threshold behaviours in GexAs(Sb)10Se90-x glasses. We found that, while the transition thresholds at MCN=2.4 and 2.67 were verified in the GeAsSe glasses, the transition thresholds can be changed to chemically stoichiometric compositions if As is substituted by Sb. We further deconvolved Raman spectra into different structural units and the change of their respective intensity showed the same behaviour, and this was ascribed to the chemical effect induced by a large difference of the atomic radius between As and Sb, and a relatively strong ionic feature of the element Sb.