Numerical study on the dynamics of a driven disordered vortex lattice

Using a model of long-range interactions between vortices, we numerically investigate the dynamics of a driven vortex lattice subject to the randomly distributed pointlike pinning centers in a thin superconducting film. At zero temperature, crossover from elastic to plastic depinnings is observed with increasing density of pinning centers. With the lattice softness, the scaling fit between force and velocity obtained in the elastic regime becomes invalid when the plastic flow appears. The peak effect occurs when one enters the plastic regime and the lattice tearing first enhances the critical current density j(c) and then suppresses it. "Steps" in the curve of velocity-force dependence and its differential are also found in the plastic regime. For the finite-temperature case, we see evidence of plastic and filamentary flow at low driving forces and temperatures. At high driving forces and low enough temperatures, evidence of an ordering of the moving vortices is seen in the flux flow regime. Our results are in agreement with all the previous simulations and recent experiments.