Processing and characterization of new oxysulfide glasses in the Ge–Ga–As–S–O system

New oxysulfide glasses have been prepared in the Ge–Ga–As system employing a two-step melting process which involves the processing of the chalcogenide glass (ChG) and its subsequent melting with amorphous GeO2 powder. Optical characterization of the synthesized oxysulfide glasses has shown that the cut-off wavelength decreases with increasing oxygen content, and this has been correlated to results of Raman and infrared (IR) spectroscopies which show the formation of new oxysulfide structural units. X-ray photoelectron spectroscopy (XPS) analysis to probe the bonding environment of oxygen atoms in the oxysulfide glass network, has revealed the preferred formation of Ga–O and Ge–O bonds in comparison to As–O bonds. This work has demonstrated that melting a ChG glass with GeO2 leads to the formation of new oxysulfide glassy materials.