Electrical Conduction in Ice

Abstract

Abstract : In an attempt to resolve the conflict existing in the literature as to dc electrical conductivity of ice, an extensive series of measurements has been made. Since surface conduction is a possible cause of some of the confusion, both bulk and surface conductivity have been measured at dc and audio-frequencies. Evidence was found for significant surface conductivity when slight contamination was present. In order to explain these results quantitatively, it is necessary to postulate a surface conduction region whose thickness varies with temperature. Extrinsic bulk conductivity due to trace impurities has been found to play an important part also and probably accounts for some of the disagreement in the literature. Using ice of the highest purity, bulk measurements show that, for a fresh sample, the dc conductivity is nearly independent of temperature down to temperatures at which the high frequency ac and dc conductivities are about equal. The results suggest that the high frequency conductivity is limited by 2 processes in parallel and that the dc conductivity is limited by the same 2 processes in series. (Author)