Superconducting slab in an antisymmetric magnetic field: Vortex–antivortex dynamics

• In this system vortex matter always consists of vortex–antivortex pairs or double kinks.
• Large critical current asymmetry ratio.
• Current polarity dependent energy barriers for flux entry and flux exit.

When a type II superconductor with slab geometry is subjected to a magnetic field which is antisymmetric with respect to the middle of the slab the induced vortex matter consists of vortex–antivortex pairs or double kinks. These double kinks and their role in the generation of a considerable asymmetry in the critical current of the slab are addressed here both numerically, in the framework of time dependent Ginzburg Landau model, and semi-analytically, using the concept of surface energy barriers for flux entry and flux exit.