Optical absorption in As-Se glasses

Abstract

The optical absorption above the fundamental edge has been measured as a function of temperature for 15 compositions from Se to AsSe. The samples were thin films made by blowing bubbles from the melt. The optical gap has a minimum near As₄₃Se₅₇. Tauc plots for absorption at different temperatures but the same composition appear to converge to a single point. An unexpected linear relation is observed between composition and the inverse square of the slopes of the Tauc plots. An inverse correlation is observed between optical gap and the glass-transition temperature.