Elastic properties of Gd3+-doped tellurovanadate glasses using pulse-echo technique

The velocity of longitudinal and transverse ultrasonic waves in different compositions of the glass system 0.65TeO(2)(0.35 - x)V2O5-xGd(2)O(3) have been measured at room temperature using the ultrasonic pulse-echo technique at 4 MHz. The velocity data of the glass system have been used to find the elastic moduli, Poisson's ratio, and Debye temperature. Some physical parameters such as the glass transition temperature and the fugacity have been calculated. The results indicated that, all of these parameters depend upon the rare-earth content. The compositional dependence of these parameters on the Gd2O3 content has been explained in terms of the bond compression model and the ring diameter model. The structure of some tellurovanadate glasses doped with various oxides of transition metals, ferroelectric materials, heavy metals and rare earth have been evaluated and discussed in terms of these two models. (C) 2004 Elsevier B.V. All rights reserved.