Conduction mechanism at high electric field and switching phenomena in V2O5-P2O5 and V2O5-P2O5-TeO2 glasses

A previous investigation [1] suggests that the conduction in some vanadate glasses is ohmic up to a field of the order of 10⁵ V cm^–1 with an activation energy range from 0.31 to 0.48 eV depending on composition, but independent of temperature above room temperature. In this work the electrical conductivity of these glasses at high electric field is reported. The results suggest that above a field of 4×10⁵ V cm^–1 conduction becomes non-ohmic, and this is found to be due to lowering the potential barrier to the carrier at high electric field. Memory switching is observed in thin blown film samples of both binary and ternary glass systems, and is associated with field-induced crystallization of a localized region and the formation of a conduction channel in the switched area due to a self-heating effect.