RESISTIVITY AND ELECTRICAL NOISE IN GRANULAR METAL COMPOSITES

A comparison of experimental results and predictions of an effective-m edium-theory model by Mantese, Curtin, and Webb has suggested that whi le the electrical conductance, in the regime where a continuous metall ic network exists, is dominated by conduction within this network, the resistance noise is dominated by intergrain tunneling. A critical exa mination of the assumptions made in their model indicates that this su ggestion is correct if the high resistance nature of the overlap regio ns between the individual grains is not considered. It is shown that b y the consideration of these regions (which is done here within the fr amework of effective-medium theories) one can account for the experime ntal data by a viable alternative which suggests that both the resisti vity and the resistance noise are dominated by the conduction througho ut the continuous metallic network.