The electrical properties of cadmium phosphate glasses at high electric fields

The cadmium phosphate glasses previously described by the authors are further examined in relation to their electrical conduction properties at high applied fields and also when the fields are sufficiently high for memory switching to occur. The conduction at high electric fields (>2×10⁴ V cm⁻¹) is believed to be due to thermally activated hopping of electrons and to field-lowering at the electrodes as predicted by Schottky. The relative significance of the Schottky and Poole-Frenkel processes is discussed. The memory switching observed in thin samples at high applied fields is shown by electron diffraction studies to be associated with field-induced crystallization of a localized region of the glass film.