Crossing lattice vortex pump

Magnetic fields tilted away from the c  -axis penetrate strongly-anisotropic layered superconductors (such as Bi2Sr2CaCu2O8+δBi2Sr2CaCu2O8+δ) as two coexisting vortex lattices: a pancake vortex (PV) stack lattice, oriented along the c  -axis, and a Josephson vortex (JV) lattice, confined between CuO2CuO2 planes. In-plane currents generated by the JVs create a symmetric and periodic pinning potential for the stacks of PVs. JVs driven by either an AC magnetic field or by a c-axis current can provide a net drift of PVs and/or JVs. Here, we employ a Fokker–Planck equation to show in detail how a strong enough c-axis current which is asymmetric in time can induce a net motion of PVs. In such a case, the oscillating JVs provide a time-averaged spatially-asymmetric potential energy which rectifies the non-equilibrium fluctuations of the PVs. We analyze the dependence of the rectification on the out-of-plane magnetic field.