Manipulation of magnetic-flux landscapes in superconducting Bi2Sr2CaCu2O8 + δ crystals

Abstract

We demonstrate experimentally that the micromagnetic profile of the out-of-plane component of magnetic induction of layered superconductors, Bz, can be manipulated by varying the in-plane magnetic field, H∥. Moving Josephson vortices, confined between layers, drag pancake vortex stacks carrying out-of-plane flux, and the magnetic profile, Bz(x), can be controllably shaped across the entire sample. Depending on the magnetic history and temperature we can increase or decrease the out-of-plane flux density at the center and near the edges of the crystal by as much as 40%, realising both “convex and concave magnetic flux lenses”. Our experimental results are well described by molecular dynamics simulations.