Er3+ and Eu3+ containing transparent glass ceramics in the system PbGeO3-PbF2-CdF2

Glasses with composition 60PbGeO(3)-10PbF(2)-30CdF(2) (mol%) have been obtained in the bulk form with a high stability against crystallization. After doping them with 0.5 mol% of Er3+ or Eu3+ and appropriate heat treatment transparent glass ceramics could be obtained. Electronic spectroscopy, X-ray diffraction and transmission electron microscopy measurements have been made. beta-PbF2: Er3+/Eu3+ Single crystals, 5-10 nm in size, are detected in the otherwise transparent composite medium, the size of the particles and absence of clustering allowing for the increased transparency of the final materials. (C) 1999 Elsevier B.V. B.V. All rights reserved.