Direct observation of the infinite percolation cluster in thin films: Evidence for a double percolation process

Abstract
Direct observation of the infinite percolation cluster at the percolation threshold is shown. We use crystallization propagation in an amorphous thin film. The morphological analysis of the infinite cluster shows good agreement with that predicted by percolation theory. The crystallization process can be described using an invasion percolation model in a fractal network. At the macroscopic scale, crystallization induces a double percolation.