Tunneling-based charge percolation transport in a random network of semi-conductive nanoclusters embedded in a dielectric matrix

The percolating tunneling transport of electrons in a random network of nanoclusters made of semi-conductive material and embedded in a dielectric matrix is studied in a simple model. Despite some strong assumptions, the model is able to reproduce results already reported in the literature, like the critical behavior of the current density at small volume fractions of nanoclusters. Due to its simplicity (e.g. contribution to the local conduction only from nearest neighbors), the model predicts a near-critical variation of the conductance which is rather close to the universal power-law behavior of a direct-contact composite material. In addition, the method can also compute total average numbers of electrons and their spatial distribution established in the sample operated in stationary regimes. Using such features of the model, optimal device configurations can be designed for optoelectronic applications.