Numerical simulations of hopping conductivity using nonflat densities of states

We report numerical simulations of hopping conduction in lightly doped semiconductors. We model the hopping using a Miller-Abrahams resistor network. We investigate the effect of the density of states (DOS) on the temperature dependence of the hopping conductivity σ(T) in a regime of temperature T well above the regime associated with variable-range hopping (VRH). In this ‘‘high-T ’’ regime, we study a ‘‘peaked’’ DOS and a ‘‘flat-flat’’ DOS. The ‘‘peaked’’ DOS has a maximum at the T=0 K chemical potential ${\mu }_0$ and decreases away from ${\mu }_0$.