Asymmetric pinning in superconductors with interpenetrating arrays of weak and strong pinning centers

Abstract

Molecular dynamics simulations of the current-voltage characteristics, V(I), have been performed for regular pinning arrays consisting of two interpenetrating triangular lattices of weak and strong pinning centers. In this case, an applied Lorentz force F L provides the depinning force which is directed either from weak to strong pinning site or vice versa, depending on the polarity of F L . This leads to a pronounced asymmetry of the critical driving force F c L needed for the vortex depinning, revealed in our numerical simulations for the vortex lattice originally coinciding with the array of strong pinning centers. The dependence of the F c L asymmetry on the shift of the two pinning sublattices is also investigated.