Numerical study of the anisotropic properties of vortex motion in superconducting films with a periodic lattice of deffects

The anisotropic effects on the dynamical phases of a vortex lattice driven by a uniform Lorentz force are investigated by numerical simulations. A square array of columnar defects is represented by a periodic pinning potential. We assume that ow is elastic, so that the vortex-vortex interactions can be represented by elastic forces. V-I characteristics and mean-square displacements and velocities for different orientations of the driving force are calculated. It is found that, for a wide range of driving force magnitude and orientation, the vortex lattice is transversely pinned in high symmetr...