Monte Carlo calculation of the current-voltage characteristics of a two   dimensional lattice Coulomb gas
  We have studied the nonlinear current-voltage characteristic of a two dimensional lattice Coulomb gas by Monte Carlo simulation. We present three different determinations of the power-law exponent $a(T)$ of the nonlinear current-voltage characteristic, $V \sim I^{a(T)+1}$. The determinations rely on both equilibrium and non-equilibrium simulations. We find good agreement between the different determinations, and our results also agree closely with experimental results for Hg-Xe thin film superconductors and for certain single crystal thin-film high temperature superconductors. 
Hans Weber, Mats Wallin and Henrik Jeldtoft Jensen