NEW FLUORO-ARSENATE GLASSES RARE-EARTH RICH

A large variety of glasses with various concentrations of rare earths can be synthesized in the fluoro-phosphate systems. To study the glass forming behavior of arsenic pentoxide in similar oxyfluoride systems, new rare-earth rich oxyfluoride glasses have been synthesized in the M2O-As2O5-BaF2-YF3 system, where M = Na or K. A large glass forming re gion has been found in the case where M = Na. Fluoride rare-earth conc entrations less than or equal to 36 mol% can be introduced in this sys tem. Physical, thermal and optical properties have been measured in th ese new glasses. (C) 1998 Elsevier Science B.V. All rights reserved.