  We have proposed an analytical model for the electrical conductivity in
random, metallic, nanowire networks. We have mimicked such random nanowire
networks as random resistor networks (RRN) produced by the homogeneous,
isotropic, and random deposition of conductive zero-width sticks onto an
insulating substrate. We studied the electrical conductivity of these RRNs
using a mean-field approximation. An analytical dependency of the electrical
conductivity on the main physical parameters (the number density and electrical
resistances of these wires and of the junctions between them) has been derived.
Computer simulations have been performed to validate our theoretical
predictions. We computed the electrical conductivity of the RRNs against the
number density of the conductive fillers for the junction-resistance-dominated
case and for the case where the wire resistance and the junction resistance
were equal. The results of the computations were compared with this mean-field
approximation. Our computations demonstrated that our analytical expression
correctly predicts the electrical conductivity across a wide range of number
densities.
