Numerical modeling of nonohmic percolation conduction and Poole–Frenkel laws

Abstract

We present a numerical model that simulates the current–voltage (I–V) characteristics of materials exhibiting percolation conduction. The model consists of a two dimensional grid of exponentially different resistors in the presence of an external electric field. We obtained exponentially nonohmic I–V characteristics validating earlier analytical predictions and consistent with multiple experimental observations of the Poole–Frenkel laws in noncrystalline materials. The exponents are linear in voltage for samples smaller than the correlation length of percolation cluster L and square root in voltage for samples larger than L.

Voltage deficit in PV with suppressed recombination

“…[7,62] It was demonstrated recently that for the case of thin films, the leaking pathways are almost rectilinear. [69] For the open circuit regime, the condition of zero total current leads to the macroscopic (average) open circuit voltage…”