Superconducting 3D Multi-layer Sample Simulated Via Nonuniform Ginzburg–Landau Parameter

Our study sample is a mesoscopic superconducting three-dimensional parallelepiped immersed in a magnetic field H z . The sample presents an anisotropy of the Ginzburg–Landau parameter κ ( z ) in the z -axis. This dependence allows us to simulate a superconducting three layer system, where the top and bottom layers are made of a type-II superconducting material, and the middle layer is fabricated of a type-I material. We analyzed the superconducting electron density, free energy, and the magnetization curves as functions of H for different values of κ ( z ) . Due to the effects of proximity and shielding on the borders of the layers, Abrikosov vortices are present in the type I regions, and a fractional vortex state is present in the type II superconducting region.