Glass forming region and optical properties of chalcogenide glasses within a gallium-tin-selenium ternary system

Abstract

In this work, glass forming region of arsenic-and germanium-free chalcogenide glasses (ChGs) within a gallium-tin-selenium (Ga-Sn-Se, GSS) ternary system is depicted. Seven representative compositions in the glass forming region are selected, and the corresponding bulk GSS glass samples are prepared for characterizing the optical properties. The experimental results show that the GSS ChGs have a wide transparent window from ~1 to 20 μm and low dispersion at both 3-5 μm and 8-12 μm mid-infrared windows. The dependence of optical bandgap energy (Eopg) on mean coordination number (MCN) indicates the existence of medium-range interactions in the GSS glass network, and its origin is investigated by the Raman spectra.