Physical model for breakdown structures in solid dielectrics

Abstract

A quantitative physical model is presented for the breakdown of solids by void or channel discharges. It is found that fractal treelike structures only occur when the ``fields'' at the growth tips are allowed to fluctuate about their Laplace values. By treating the local-field enhancement factor as a white noise produced by the breakdown mechanism itself, it is shown that the amount of branching depends only on the range of fluctuations allowed.