Driven diffusion in the two-dimensional lattice Coulomb gas: A model for flux flow in superconducting networks.

We carry out driven-diffusion Monte Carlo simulations of the two-dimensional classical lattice Coulomb gas in an applied uniform electric field, as a model for vortex motion due to an applied dc current in a periodic superconducting network. A finite-size version of dynamic scaling is used to extract the dynamic critical exponent [ital z], and infer the nonlinear response at the transition temperature. We consider the Coulomb gases [ital f]=0 and [ital f]=1/2, corresponding to a superconducting network with an applied transverse magnetic field of zero, and one-half flux quantum per unit cell, respectively.