AC CONDUCTIVITY FOR AMORPHOUS TEO2-P2O5 GLASS SYSTEM

The a.c. conductivity for the TeO2-P2O5 glassy system was measured in the temperature range 300-573 K and in the frequency range 100 Hz to 1 0 kHz. The a.c. conductivity sigma(omega) increased with frequency acc ording to the relation sigma(omega)alphaomega(s). The frequency expone nt s was found to decrease with increasing temperature. The compositio n dependence of the conductivity was also investigated. The density of states was also calculated using the Elliott model. The a.c. conducti vity increased over the studied temperature range. The obtained experi mental data have been analysed with reference to various theoretical m odels. The analysis shows that the correlated barrier hopping (CBH) mo del is the most appropriate mechanism for conduction in the TeO2-P2O5 glass system.