Space Charge and Electrode Polarization in Glass, II

Abstract

This paper is Part IT of a two‐part series reviewing the present understanding of space charge and electrode polarization in glass and the interrelations of these concepts with the usually measured electrical properties of glass. Emphasis is placed on a theory describing the distribution of static space charge in material having only a single mobile charge carrier. Charge dissociation and recombination are considered and the carriers are assumed to move under diffusion and conduction. The charge distributions predicted by the theory are discussed and are compared with the results of experiments which were undertaken specifically to verify essential features of the predictions. The theory is confirmed qualitatively by the observed charge distribution shapes and asymmetries. Quantitative confirmation is also shown in computed values of mobility, diffusion constant, and contact potential ratios. This theory has here been expanded to include a linearized ac treatment, and the phenomena predicted by this treatment fit the known data semi‐quantitatively. A large low‐frequency relaxation mechanism is predicted. Previous theory and experiment were briefly reviewed in Part I. In Part I1 the predicted and observed space charges are conceptually related to various phenomena such as conduction, electrode polarization, dielectric absorption, and dielectric loss. Needed improvements in the present theory and a number of ideas for more experiments are outlined in order to stimulate efforts to acquire a more detailed understanding of these phenomena.