Monte Carlo simulation of transient currents induced by a random walk on percolation clusters

The transient current induced by the random walk of particles in site percolation clusters in a 30 × 30 × 30 simple-cubic lattice is calculated with the Monte Carlo technique. The calculated transient current could be fitted by a pair of hyperbolic decay functions and can describe the dispersive transient currents observed in time-of-flight experiment on amorphous semiconductors. We have found that the dispersion parameter α1 calculated for incipient percolation clusters is given by δ/đ, where đ and δ are the fractal and fracton dimensions, respectively.