Optical properties of Ge-Te-Ga doping Al and AlCl3 far infrared transmitting chalcogenide glasses

► Studied glass samples all have wide IR transmission window from 1.8Ge to Te20 μm. ► Ge15Te75Ga10Al4 glass shows superior thermal stability (△T=126 °C). ► The absorption peak involving Ga-O bond disappears after Al or AlCl3 doping. ► △T of AlCl3 doped glasses keep all over 100 °C and have small fluctuation.