Basic Physical Analysis of New Sb-se-ge-in Chalcogenide Glassy Alloys by Predicting Structural Units: A Theoretical Approach

Abstract

Low transmission losses, semiconducting and phase change properties of chalcogenides make them attractive candidates to be used in all-optical devices [1], conducting chalcogenide glass sensors [2] and phase change memory devices [3] etc. SbSeGe glasses have possible applications in IR optical fibers because of their large bandgap, low material dispersion, low light scattering and long wavelength multiphonon edge [4, 5]. For 25 at. % of Ge alloying in Sb10Se90- xGex glass alloys a more rigid composition is obtained [6, 7]. This composition contains only heteropolar Ge-Se and Sb-Se bonds. Sb10Se65Ge25 has been alloyed with In to investigate Sb10Se65Ge25-yIny (y = 0, 3, 6, 9, 12, 15) system via different physical parameters. Sharma et al. have reported that In addition increases the dark conductivity due to an increase in the number of defect states [8]. It has also been reported that In alloying decreases the optical energy band gap [9], suitable to explore the system for optoelectronic devices, and thermal activation energy [10] of the systems. These results motivate us to study the In alloying on Sb10Se65Ge25 glass alloy. Due to large electronegativity difference between Ge and In, there is a possibility of increase in the glass forming region and In may also bring configurational and conformal changes in the base system.