Simulation study on Hall effect in logarithmically interacting vortex system

We simulate the current-driven vortex motion in a two-dimensional square sample of type-II superconductors, by using a logarithmically interacting point vortex model involving effect of temperature, transport current, random pinning centers, magnetic field, and Magnus force. We also take into account both the vortex pair nucleation and the vortex pair annihilation processes in the model. Simulation results show that the negative Hall effect is observed for a certain range of the model parameters. Such an anomalous behavior is thought to originate from freely moving antivortices with the long life-time due to the collective dynamics of this vortex system on the background of weakly pinned vortex lattice.